Mobile DNAPub Date : 2024-05-06DOI: 10.1186/s13100-024-00319-8
Valentina Peona, Jacopo Martelossi, Dareen Almojil, Julia Bocharkina, Ioana Brännström, Max Brown, Alice Cang, Tomàs Carrasco-Valenzuela, Jon DeVries, Meredith Doellman, Daniel Elsner, Pamela Espíndola-Hernández, Guillermo Friis Montoya, Bence Gaspar, Danijela Zagorski, Paweł Hałakuc, Beti Ivanovska, Christopher Laumer, Robert Lehmann, Ljudevit Luka Boštjančić, Rahia Mashoodh, Sofia Mazzoleni, Alice Mouton, Maria Anna Nilsson, Yifan Pei, Giacomo Potente, Panagiotis Provataris, José Ramón Pardos-Blas, Ravindra Raut, Tomasa Sbaffi, Florian Schwarz, Jessica Stapley, Lewis Stevens, Nusrat Sultana, Radka Symonova, Mohadeseh S Tahami, Alice Urzì, Heidi Yang, Abdullah Yusuf, Carlo Pecoraro, Alexander Suh
{"title":"Teaching transposon classification as a means to crowd source the curation of repeat annotation - a tardigrade perspective.","authors":"Valentina Peona, Jacopo Martelossi, Dareen Almojil, Julia Bocharkina, Ioana Brännström, Max Brown, Alice Cang, Tomàs Carrasco-Valenzuela, Jon DeVries, Meredith Doellman, Daniel Elsner, Pamela Espíndola-Hernández, Guillermo Friis Montoya, Bence Gaspar, Danijela Zagorski, Paweł Hałakuc, Beti Ivanovska, Christopher Laumer, Robert Lehmann, Ljudevit Luka Boštjančić, Rahia Mashoodh, Sofia Mazzoleni, Alice Mouton, Maria Anna Nilsson, Yifan Pei, Giacomo Potente, Panagiotis Provataris, José Ramón Pardos-Blas, Ravindra Raut, Tomasa Sbaffi, Florian Schwarz, Jessica Stapley, Lewis Stevens, Nusrat Sultana, Radka Symonova, Mohadeseh S Tahami, Alice Urzì, Heidi Yang, Abdullah Yusuf, Carlo Pecoraro, Alexander Suh","doi":"10.1186/s13100-024-00319-8","DOIUrl":"10.1186/s13100-024-00319-8","url":null,"abstract":"<p><strong>Background: </strong>The advancement of sequencing technologies results in the rapid release of hundreds of new genome assemblies a year providing unprecedented resources for the study of genome evolution. Within this context, the significance of in-depth analyses of repetitive elements, transposable elements (TEs) in particular, is increasingly recognized in understanding genome evolution. Despite the plethora of available bioinformatic tools for identifying and annotating TEs, the phylogenetic distance of the target species from a curated and classified database of repetitive element sequences constrains any automated annotation effort. Moreover, manual curation of raw repeat libraries is deemed essential due to the frequent incompleteness of automatically generated consensus sequences.</p><p><strong>Results: </strong>Here, we present an example of a crowd-sourcing effort aimed at curating and annotating TE libraries of two non-model species built around a collaborative, peer-reviewed teaching process. Manual curation and classification are time-consuming processes that offer limited short-term academic rewards and are typically confined to a few research groups where methods are taught through hands-on experience. Crowd-sourcing efforts could therefore offer a significant opportunity to bridge the gap between learning the methods of curation effectively and empowering the scientific community with high-quality, reusable repeat libraries.</p><p><strong>Conclusions: </strong>The collaborative manual curation of TEs from two tardigrade species, for which there were no TE libraries available, resulted in the successful characterization of hundreds of new and diverse TEs in a reasonable time frame. Our crowd-sourcing setting can be used as a teaching reference guide for similar projects: A hidden treasure awaits discovery within non-model organisms.</p>","PeriodicalId":18854,"journal":{"name":"Mobile DNA","volume":"15 1","pages":"10"},"PeriodicalIF":4.9,"publicationDate":"2024-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11071193/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140874740","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mobile DNAPub Date : 2024-05-04DOI: 10.1186/s13100-024-00320-1
Elena Fernández-Suárez, María González-del Pozo, Cristina Méndez-Vidal, Marta Martín-Sánchez, Marcela Mena, Belén de la Morena-Barrio, Javier Corral, Salud Borrego, Guillermo Antiñolo
{"title":"Long-read sequencing improves the genetic diagnosis of retinitis pigmentosa by identifying an Alu retrotransposon insertion in the EYS gene","authors":"Elena Fernández-Suárez, María González-del Pozo, Cristina Méndez-Vidal, Marta Martín-Sánchez, Marcela Mena, Belén de la Morena-Barrio, Javier Corral, Salud Borrego, Guillermo Antiñolo","doi":"10.1186/s13100-024-00320-1","DOIUrl":"https://doi.org/10.1186/s13100-024-00320-1","url":null,"abstract":"Biallelic variants in EYS are the major cause of autosomal recessive retinitis pigmentosa (arRP) in certain populations, a clinically and genetically heterogeneous disease that may lead to legal blindness. EYS is one of the largest genes (~ 2 Mb) expressed in the retina, in which structural variants (SVs) represent a common cause of disease. However, their identification using short-read sequencing (SRS) is not always feasible. Here, we conducted targeted long-read sequencing (T-LRS) using adaptive sampling of EYS on the MinION sequencing platform (Oxford Nanopore Technologies) to definitively diagnose an arRP family, whose affected individuals (n = 3) carried the heterozygous pathogenic deletion of exons 32–33 in the EYS gene. As this was a recurrent variant identified in three additional families in our cohort, we also aimed to characterize the known deletion at the nucleotide level to assess a possible founder effect. T-LRS in family A unveiled a heterozygous AluYa5 insertion in the coding exon 43 of EYS (chr6(GRCh37):g.64430524_64430525ins352), which segregated with the disease in compound heterozygosity with the previously identified deletion. Visual inspection of previous SRS alignments using IGV revealed several reads containing soft-clipped bases, accompanied by a slight drop in coverage at the Alu insertion site. This prompted us to develop a simplified program using grep command to investigate the recurrence of this variant in our cohort from SRS data. Moreover, LRS also allowed the characterization of the CNV as a ~ 56.4kb deletion spanning exons 32–33 of EYS (chr6(GRCh37):g.64764235_64820592del). The results of further characterization by Sanger sequencing and linkage analysis in the four families were consistent with a founder variant. To our knowledge, this is the first report of a mobile element insertion into the coding sequence of EYS, as a likely cause of arRP in a family. Our study highlights the value of LRS technology in characterizing and identifying hidden pathogenic SVs, such as retrotransposon insertions, whose contribution to the etiopathogenesis of rare diseases may be underestimated.","PeriodicalId":18854,"journal":{"name":"Mobile DNA","volume":"112 1","pages":""},"PeriodicalIF":4.9,"publicationDate":"2024-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140833711","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mobile DNAPub Date : 2024-04-16DOI: 10.1186/s13100-024-00317-w
Anthony B. Garza, Emmanuelle Lerat, Hani Z. Girgis
{"title":"Look4LTRs: a Long terminal repeat retrotransposon detection tool capable of cross species studies and discovering recently nested repeats","authors":"Anthony B. Garza, Emmanuelle Lerat, Hani Z. Girgis","doi":"10.1186/s13100-024-00317-w","DOIUrl":"https://doi.org/10.1186/s13100-024-00317-w","url":null,"abstract":"Plant genomes include large numbers of transposable elements. One particular type of these elements is flanked by two Long Terminal Repeats (LTRs) and can translocate using RNA. Such elements are known as LTR-retrotransposons; they are the most abundant type of transposons in plant genomes. They have many important functions involving gene regulation and the rise of new genes and pseudo genes in response to severe stress. Additionally, LTR-retrotransposons have several applications in biotechnology. Due to the abundance and the importance of LTR-retrotransposons, multiple computational tools have been developed for their detection. However, none of these tools take advantages of the availability of related genomes; they process one chromosome at a time. Further, recently nested LTR-retrotransposons (multiple elements of the same family are inserted into each other) cannot be annotated accurately — or cannot be annotated at all — by the currently available tools. Motivated to overcome these two limitations, we built Look4LTRs, which can annotate LTR-retrotransposons in multiple related genomes simultaneously and discover recently nested elements. The methodology of Look4LTRs depends on techniques imported from the signal-processing field, graph algorithms, and machine learning with a minimal use of alignment algorithms. Four plant genomes were used in developing Look4LTRs and eight plant genomes for evaluating it in contrast to three related tools. Look4LTRs is the fastest while maintaining better or comparable F1 scores (the harmonic average of recall and precision) to those obtained by the other tools. Our results demonstrate the added benefit of annotating LTR-retrotransposons in multiple related genomes simultaneously and the ability to discover recently nested elements. Expert human manual examination of six elements — not included in the ground truth — revealed that three elements belong to known families and two elements are likely from new families. With respect to examining recently nested LTR-retrotransposons, three out of five were confirmed to be valid elements. Look4LTRs — with its speed, accuracy, and novel features — represents a true advancement in the annotation of LTR-retrotransposons, opening the door to many studies focused on understanding their functions in plants.","PeriodicalId":18854,"journal":{"name":"Mobile DNA","volume":"57 1","pages":""},"PeriodicalIF":4.9,"publicationDate":"2024-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140570258","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mobile DNAPub Date : 2024-04-11DOI: 10.1186/s13100-024-00318-9
Nozhat T. Hassan, James D. Galbraith, David L. Adelson
{"title":"Multiple horizontal transfer events of a DNA transposon into turtles, fishes, and a frog","authors":"Nozhat T. Hassan, James D. Galbraith, David L. Adelson","doi":"10.1186/s13100-024-00318-9","DOIUrl":"https://doi.org/10.1186/s13100-024-00318-9","url":null,"abstract":"Horizontal transfer of transposable elements (HTT) has been reported across many species and the impact of such events on genome structure and function has been well described. However, few studies have focused on reptilian genomes, especially HTT events in Testudines (turtles). Here, as a consequence of investigating the repetitive content of Malaclemys terrapin terrapin (Diamondback turtle) we found a high similarity DNA transposon, annotated in RepBase as hAT-6_XT, shared between other turtle species, ray-finned fishes, and a frog. hAT-6_XT was notably absent in reptilian taxa closely related to turtles, such as crocodiles and birds. Successful invasion of DNA transposons into new genomes requires the conservation of specific residues in the encoded transposase, and through structural analysis, these residues were identified indicating some retention of functional transposition activity. We document six recent independent HTT events of a DNA transposon in turtles, which are known to have a low genomic evolutionary rate and ancient repeats. Malaclemys terrapin terrapin (Diamondback turtle). Malaclemys terrapin pileata (Mississippi diamondback terrapin turtle). Trachemys scripta elegans (Red-eared slider turtle). Chrysemys picta bellii (Western painted turtle). Dermatemys mawii (Hickatee turtle). Sternotherus odoratus (Common musk turtle). Mesoclemmys tuberculata (Tuberculate Toad-headed turtle). Etheostoma spectabile (Orangethroat darter fish). Thalassophryne amazonica (Prehistoric monster fish). Scophthalmus maximus (Turbot fish). Syngnathus acus (Greater pipefish). Scleropages formosus (Asian Arowana fish). Xenopus tropicalis (Western clawed frog).","PeriodicalId":18854,"journal":{"name":"Mobile DNA","volume":"60 1","pages":""},"PeriodicalIF":4.9,"publicationDate":"2024-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140570065","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mobile DNAPub Date : 2024-04-03DOI: 10.1186/s13100-024-00315-y
Michel Choudalakis, Pavel Bashtrykov, Albert Jeltsch
{"title":"RepEnTools: an automated repeat enrichment analysis package for ChIP-seq data reveals hUHRF1 Tandem-Tudor domain enrichment in young repeats","authors":"Michel Choudalakis, Pavel Bashtrykov, Albert Jeltsch","doi":"10.1186/s13100-024-00315-y","DOIUrl":"https://doi.org/10.1186/s13100-024-00315-y","url":null,"abstract":"Repeat elements (REs) play important roles for cell function in health and disease. However, RE enrichment analysis in short-read high-throughput sequencing (HTS) data, such as ChIP-seq, is a challenging task. Here, we present RepEnTools, a software package for genome-wide RE enrichment analysis of ChIP-seq and similar chromatin pulldown experiments. Our analysis package bundles together various software with carefully chosen and validated settings to provide a complete solution for RE analysis, starting from raw input files to tabular and graphical outputs. RepEnTools implementations are easily accessible even with minimal IT skills (Galaxy/UNIX). To demonstrate the performance of RepEnTools, we analysed chromatin pulldown data by the human UHRF1 TTD protein domain and discovered enrichment of TTD binding on young primate and hominid specific polymorphic repeats (SVA, L1PA1/L1HS) overlapping known enhancers and decorated with H3K4me1-K9me2/3 modifications. We corroborated these new bioinformatic findings with experimental data by qPCR assays using newly developed primate and hominid specific qPCR assays which complement similar research tools. Finally, we analysed mouse UHRF1 ChIP-seq data with RepEnTools and showed that the endogenous mUHRF1 protein colocalizes with H3K4me1-H3K9me3 on promoters of REs which were silenced by UHRF1. These new data suggest a functional role for UHRF1 in silencing of REs that is mediated by TTD binding to the H3K4me1-K9me3 double mark and conserved in two mammalian species. RepEnTools improves the previously available programmes for RE enrichment analysis in chromatin pulldown studies by leveraging new tools, enhancing accessibility and adding some key functions. RepEnTools can analyse RE enrichment rapidly, efficiently, and accurately, providing the community with an up-to-date, reliable and accessible tool for this important type of analysis.","PeriodicalId":18854,"journal":{"name":"Mobile DNA","volume":"82 1","pages":""},"PeriodicalIF":4.9,"publicationDate":"2024-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140570063","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mobile DNAPub Date : 2024-03-15DOI: 10.1186/s13100-024-00316-x
Xuanzeng Liu, Lina Zhao, Muhammad Majid, Yuan Huang
{"title":"Orthoptera-TElib: a library of Orthoptera transposable elements for TE annotation.","authors":"Xuanzeng Liu, Lina Zhao, Muhammad Majid, Yuan Huang","doi":"10.1186/s13100-024-00316-x","DOIUrl":"10.1186/s13100-024-00316-x","url":null,"abstract":"<p><p>Transposable elements (TEs) are a major component of eukaryotic genomes and are present in almost all eukaryotic organisms. TEs are highly dynamic between and within species, which significantly affects the general applicability of the TE databases. Orthoptera is the only known group in the class Insecta with a significantly enlarged genome (0.93-21.48 Gb). When analyzing the large genome using the existing TE public database, the efficiency of TE annotation is not satisfactory. To address this limitation, it becomes imperative to continually update the available TE resource library and the need for an Orthoptera-specific library as more insect genomes are publicly available. Here, we used the complete genome data of 12 Orthoptera species to de novo annotate TEs, then manually re-annotate the unclassified TEs to construct a non-redundant Orthoptera-specific TE library: Orthoptera-TElib. Orthoptera-TElib contains 24,021 TE entries including the re-annotated results of 13,964 unknown TEs. The naming of TE entries in Orthoptera-TElib adopts the same naming as RepeatMasker and Dfam and is encoded as the three-level form of \"level1/level2-level3\". Orthoptera-TElib can be directly used as an input reference database and is compatible with mainstream repetitive sequence analysis software such as RepeatMasker and dnaPipeTE. When analyzing TEs of Orthoptera species, Orthoptera-TElib performs better TE annotation as compared to Dfam and Repbase regardless of using low-coverage sequencing or genome assembly data. The most improved TE annotation result is Angaracris rhodopa, which has increased from 7.89% of the genome to 53.28%. Finally, Orthoptera-TElib is stored in Sqlite3 for the convenience of data updates and user access.</p>","PeriodicalId":18854,"journal":{"name":"Mobile DNA","volume":"15 1","pages":"5"},"PeriodicalIF":4.9,"publicationDate":"2024-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10941475/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140132076","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mobile DNAPub Date : 2024-03-11DOI: 10.1186/s13100-024-00314-z
Igor Bren, Ayellet Tal, Carmit Strauss, Sharon Schlesinger
{"title":"The role of Smarcad1 in retroviral repression in mouse embryonic stem cells","authors":"Igor Bren, Ayellet Tal, Carmit Strauss, Sharon Schlesinger","doi":"10.1186/s13100-024-00314-z","DOIUrl":"https://doi.org/10.1186/s13100-024-00314-z","url":null,"abstract":"Moloney murine leukemia virus (MLV) replication is suppressed in mouse embryonic stem cells (ESCs) by the Trim28-SETDB1 complex. The chromatin remodeler Smarcad1 interacts with Trim28 and was suggested to allow the deposition of the histone variant H3.3. However, the role of Trim28, H3.3, and Smarcad1 in MLV repression in ESCs still needs to be fully understood. In this study, we used MLV to explore the role of Smarcad1 in retroviral silencing in ESCs. We show that Smarcad1 is immediately recruited to the MLV provirus. Based on the repression dynamics of a GFP-reporter MLV, our findings suggest that Smarcad1 plays a critical role in the establishment and maintenance of MLV repression, as well as other Trim28-targeted genomic loci. Furthermore, Smarcad1 is important for stabilizing and strengthening Trim28 binding to the provirus over time, and its presence around the provirus is needed for proper deposition of H3.3 on the provirus. Surprisingly, the combined depletion of Smarcad1 and Trim28 results in enhanced MLV derepression, suggesting that these two proteins may also function independently to maintain repressive chromatin states. Overall, the results of this study provide evidence for the crucial role of Smarcad1 in the silencing of retroviral elements in embryonic stem cells. Further research is needed to fully understand how Smarcad1 and Trim28 cooperate and their implications for gene expression and genomic stability.","PeriodicalId":18854,"journal":{"name":"Mobile DNA","volume":"90 1","pages":""},"PeriodicalIF":4.9,"publicationDate":"2024-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140099340","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"CRISPR-TE: a web-based tool to generate single guide RNAs targeting transposable elements","authors":"Yixin Guo, Ziwei Xue, Meiting Gong, Siqian Jin, Xindi Wu, Wanlu Liu","doi":"10.1186/s13100-024-00313-0","DOIUrl":"https://doi.org/10.1186/s13100-024-00313-0","url":null,"abstract":"The CRISPR/Cas systems have emerged as powerful tools in genome engineering. Recent studies highlighting the crucial role of transposable elements (TEs) have stimulated research interest in manipulating these elements to understand their functions. However, designing single guide RNAs (sgRNAs) that are specific and efficient for TE manipulation is a significant challenge, given their sequence repetitiveness and high copy numbers. While various sgRNA design tools have been developed for gene editing, an optimized sgRNA designer for TE manipulation has yet to be established. We present CRISPR-TE, a web-based application featuring an accessible graphical user interface, available at https://www.crisprte.cn/ , and currently tailored to the human and mouse genomes. CRISPR-TE identifies all potential sgRNAs for TEs and provides a comprehensive solution for efficient TE targeting at both the single copy and subfamily levels. Our analysis shows that sgRNAs targeting TEs can more effectively target evolutionarily young TEs with conserved sequences at the subfamily level. CRISPR-TE offers a versatile framework for designing sgRNAs for TE targeting. CRISPR-TE is publicly accessible at https://www.crisprte.cn/ as an online web service and the source code of CRISPR-TE is available at https://github.com/WanluLiuLab/CRISPRTE/ .","PeriodicalId":18854,"journal":{"name":"Mobile DNA","volume":"67 1","pages":""},"PeriodicalIF":4.9,"publicationDate":"2024-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139656551","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mobile DNAPub Date : 2024-01-20DOI: 10.1186/s13100-024-00312-1
Ursula Oggenfuss, Thomas Badet, Daniel Croll
{"title":"A systematic screen for co-option of transposable elements across the fungal kingdom","authors":"Ursula Oggenfuss, Thomas Badet, Daniel Croll","doi":"10.1186/s13100-024-00312-1","DOIUrl":"https://doi.org/10.1186/s13100-024-00312-1","url":null,"abstract":"How novel protein functions are acquired is a central question in molecular biology. Key paths to novelty include gene duplications, recombination or horizontal acquisition. Transposable elements (TEs) are increasingly recognized as a major source of novel domain-encoding sequences. However, the impact of TE coding sequences on the evolution of the proteome remains understudied. Here, we analyzed 1237 genomes spanning the phylogenetic breadth of the fungal kingdom. We scanned proteomes for evidence of co-occurrence of TE-derived domains along with other conventional protein functional domains. We detected more than 13,000 predicted proteins containing potentially TE-derived domain, of which 825 were identified in more than five genomes, indicating that many host-TE fusions may have persisted over long evolutionary time scales. We used the phylogenetic context to identify the origin and retention of individual TE-derived domains. The most common TE-derived domains are helicases derived from Academ, Kolobok or Helitron. We found putative TE co-options at a higher rate in genomes of the Saccharomycotina, providing an unexpected source of protein novelty in these generally TE depleted genomes. We investigated in detail a candidate host-TE fusion with a heterochromatic transcriptional silencing function that may play a role in TE and gene regulation in ascomycetes. The affected gene underwent multiple full or partial losses within the phylum. Overall, our work establishes a kingdom-wide view of putative host-TE fusions and facilitates systematic investigations of candidate fusion proteins.","PeriodicalId":18854,"journal":{"name":"Mobile DNA","volume":"42 1","pages":""},"PeriodicalIF":4.9,"publicationDate":"2024-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139508038","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mobile DNAPub Date : 2024-01-13DOI: 10.1186/s13100-023-00311-8
Ivar Westerberg, S. Lorena Ament-Velásquez, Aaron A. Vogan, Hanna Johannesson
{"title":"Evolutionary dynamics of the LTR-retrotransposon crapaud in the Podospora anserina species complex and the interaction with repeat-induced point mutations","authors":"Ivar Westerberg, S. Lorena Ament-Velásquez, Aaron A. Vogan, Hanna Johannesson","doi":"10.1186/s13100-023-00311-8","DOIUrl":"https://doi.org/10.1186/s13100-023-00311-8","url":null,"abstract":"The genome of the filamentous ascomycete Podospora anserina shows a relatively high abundance of retrotransposons compared to other interspersed repeats. The LTR-retrotransposon family crapaud is particularly abundant in the genome, and consists of multiple diverged sequence variations specifically localized in the 5’ half of both long terminal repeats (LTRs). P. anserina is part of a recently diverged species-complex, which makes the system ideal to classify the crapaud family based on the observed LTR variation and to study the evolutionary dynamics, such as the diversification and bursts of the elements over recent evolutionary time. We developed a sequence similarity network approach to classify the crapaud repeats of seven genomes representing the P. anserina species complex into 14 subfamilies. This method does not utilize a consensus sequence, but instead it connects any copies that share enough sequence similarity over a set sequence coverage. Based on phylogenetic analyses, we found that the crapaud repeats likely diversified in the ancestor of the complex and have had activity at different time points for different subfamilies. Furthermore, while we hypothesized that the evolution into multiple subfamilies could have been a direct effect of escaping the genome defense system of repeat induced point mutations, we found this not to be the case. Our study contributes to the development of methods to classify transposable elements in fungi, and also highlights the intricate patterns of retrotransposon evolution over short timescales and under high mutational load caused by nucleotide-altering genome defense.","PeriodicalId":18854,"journal":{"name":"Mobile DNA","volume":"127 1","pages":""},"PeriodicalIF":4.9,"publicationDate":"2024-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139464392","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}