BMC Biology最新文献

{"title":"Pre- and post-copulatory traits are affected by experimental inbreeding, but they are not correlated.","authors":"Doris Nicolakis, Maria Adelaide Marconi, Kerstin E Auer, Dustin J Penn, Sarah M Zala","doi":"10.1186/s12915-025-02245-4","DOIUrl":"10.1186/s12915-025-02245-4","url":null,"abstract":"<p><strong>Background: </strong>It has been suggested that the expression of males' secondary sexual traits provides reliable indicators of their sperm traits, predicting positive correlations between pre- and post-copulatory traits (Fertility Indicator Hypothesis). Yet, it has also been suggested that males face life-history tradeoffs between investing into primary versus secondary sexual traits, predicting negative correlations (Sexual Allocation Tradeoff Hypothesis). These two hypotheses are not mutually exclusive when males' sexual traits are condition-dependent and high-quality males are better able to invest into both pre- and post-copulatory traits than low-quality males. To test these hypotheses, we manipulated the genetic quality of wild-derived male house mice by experimental inbreeding and first tested whether inbreeding affects primary or secondary sexual traits (condition-dependent expression). We then tested whether pre- and post-copulatory traits are correlated. We recorded courtship behavior and vocalizations of the males during female contact and measured males' reproductive organs, sperm quality, and the expression of four genes associated with spermatogenesis.</p><p><strong>Results: </strong>Inbreeding did not reduce male courtship vocalizations, though it altered their vocal repertoire and reduced other courtship behaviors. Inbreeding negatively impacted relative testes mass and sperm quantity and quality, after two generations of inbreeding. We found no consistent correlations between pre-and post-copulatory traits, either positive or negative, regardless of inbreeding.</p><p><strong>Conclusions: </strong>Our results indicate that inbreeding impacted the expression of primary and secondary sexual traits in wild-derived house mice, which is the first such evidence to our knowledge, but we found no support for either the Fertility Indicator or the Sexual Allocation Tradeoff Hypotheses.</p>","PeriodicalId":9339,"journal":{"name":"BMC Biology","volume":"23 1","pages":"144"},"PeriodicalIF":4.4,"publicationDate":"2025-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12121127/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144172776","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Juvenile hormone and BMP signaling modulate fat body cell fate during the transition of previtellogenic development to vitellogenesis.","authors":"Zhongxia Wu, Wenxiao Zhao, Mengyao Lang, Qiongjie He, Yiying Li, Yuanyuan Hu, Yan Liu, Siqian Zheng, Huanhuan Shi, Shutang Zhou","doi":"10.1186/s12915-025-02247-2","DOIUrl":"10.1186/s12915-025-02247-2","url":null,"abstract":"<p><strong>Background: </strong>Insect fat body, a central tissue for nutrient storage, energy metabolism, and protein synthesis, degrades by apoptosis and autophagy during larval metamorphosis. After adult emergence, the fat body grows rapidly with cell proliferation and polyploidization during the previtellogenic period but ceases cell proliferation in the vitellogenic phase. So far, the regulatory mechanisms underlying fat body cell fate decisions in adulthood remain unknown.</p><p><strong>Results: </strong>Transcriptomic analysis of locust fat body revealed the enrichment of pathways associated with cell cycle, nuclear division, and DNA replication. Decapentaplegic (Dpp) was among the top of differentially expressed genes in the signaling cascades involved in regulating cell proliferation. Abundance of Dpp, phosphorylated Mad (p-Mad), and Medea increased during the previtellogenic stage and subsequently declined in the vitellogenic phase. Knockdown of Dpp, Mad, and Medea resulted in suppressed fat body cell proliferation, along with remarkably reduced cell number and blocked vitellogenin (Vg) expression in the fat body as well as consequent arrest of egg development. Mad/Medea complex bound to the promoters of cyclin B (CycB) and polo-like kinase 1 (Plk1) and stimulated their expression. Depletion of CycB and Plk1 caused the defective phenotypes resembling Dpp, Mad, and Medea knockdown. In the vitellogenic phase, the high levels of juvenile hormone (JH) promoted the degradation of Medea via fizzy-related protein (Fzr)-mediated ubiquitination, leading to inhibited cell proliferation. The results suggest that fat body cell proliferation in the previtellogenic development is promoted by the bone morphogenetic protein (BMP) signaling pathway, whereas high levels of JH in the vitellogenic stage antagonize BMP signaling for ceasing cell proliferation.</p><p><strong>Conclusions: </strong>The findings provide novel insights into the regulation of fat body cell fate during the transition of previtellogenic growth to vitellogenic Vg synthesis for reproductive requirements.</p>","PeriodicalId":9339,"journal":{"name":"BMC Biology","volume":"23 1","pages":"143"},"PeriodicalIF":4.4,"publicationDate":"2025-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12121051/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144172788","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"RNA multi-omics in single cells reveal rhythmical RNA reshaping during human and mouse oocyte maturation.","authors":"Huan Yao, Danru Zhang, Haixia Jin, Yanjie Guo, Yan Liu, Shengnan Wang, Tong Li, Shenli Yuan, Gang Lu, Yingpu Sun","doi":"10.1186/s12915-025-02250-7","DOIUrl":"10.1186/s12915-025-02250-7","url":null,"abstract":"<p><strong>Background: </strong>Omics technologies are widely applied in assisted reproductive technology (ART), such as embryo selection, investigation of infertility causes, and mechanisms underlying reproductive cell development. While RNAomics has shown great potential in investigating the physiology and pathology in female reproductive system, its applications are still not fully developed. More studies on epitranscriptomic regulation mechanisms and novel sequencing methods are needed to advance the field.</p><p><strong>Results: </strong>Here, we developed a method named Cap to Tail sequencing application (C2T-APP) and simultaneously characterized the m⁷G cap, poly(A) tail structure, and gene expression level for the intact RNA molecules in single cells. C2T-APP distinguished the N6, 2'-O-dimethyladenosine modification (m⁶A_m) from N⁶-methyladenosine (m⁶A) modification with our published single-cell m⁶A sequencing (scm⁶A-seq) data. During oocyte maturation, we found a positive correlation of m⁷G and m⁶A_m with translation efficiency and finely dissected the step-wised maternal RNA de-capping and de-tailing of different types of genes. Strikingly, we uncovered a subtle structural mechanism regulating poly(A) tails in oocytes: maternal RNA translation is temporarily suppressed by removing the poly(A) tails without complete degradation, while the poly(A)-tail regulators themselves depend strictly on translation initiated after meiotic resumption. Furthermore, we profiled single-cell RNA-multi-omic features of human oocytes with different qualities during in vitro culture maturation (IVM). Defects of epi-transcriptome features, including m⁶A, m⁶A_m, m⁷G, and poly(A) structure of maternal RNA in the oocytes with poor quality, were detected.</p><p><strong>Conclusions: </strong>Our results provided a valuable tool for RNAomics research and data resources provided novel insights into human oocyte maturation, which is helpful for IVM and oocyte selection for ART.</p>","PeriodicalId":9339,"journal":{"name":"BMC Biology","volume":"23 1","pages":"147"},"PeriodicalIF":4.4,"publicationDate":"2025-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12121112/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144172722","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"NeuroScale: evolutional scale-based protein language models enable prediction of neuropeptides.","authors":"Hongqi Zhang, Shanghua Liu, Wei Su, Xueqin Xie, Junwen Yu, Fuying Dao, Mi Yang, Hao Lyu, Hao Lin","doi":"10.1186/s12915-025-02243-6","DOIUrl":"10.1186/s12915-025-02243-6","url":null,"abstract":"<p><strong>Background: </strong>Neuropeptides (NPs) are critical signaling molecules involved in various physiological and behavioral processes, including development, metabolism, and memory. They function within both the nervous and endocrine systems and have emerged as promising therapeutic targets for a range of diseases. Despite their significance, the accurate identification of NPs remains a challenge, necessitating the development of more effective computational approaches.</p><p><strong>Results: </strong>In this study, we introduce NeuroScale, a multi-channel neural network model leveraging evolutionary scale modeling (ESM) for the precise prediction of NPs. By integrating the GoogLeNet framework, NeuroScale effectively captures multi-scale NP features, enabling robust and accurate classification. Extensive benchmarking demonstrates its superior performance, consistently achieving an area under the receiver operating characteristic curve (AUC) exceeding 0.97. Additionally, we systematically analyzed the impact of protein sequence similarity thresholds and multi-scale sequence lengths on model performance, further validating NeuroScale's robustness and generalizability.</p><p><strong>Conclusions: </strong>NeuroScale represents a significant advancement in neuropeptide prediction, offering both high accuracy and adaptability to diverse sequence characteristics. Its ability to generalize across different sequence similarity thresholds and lengths underscores its potential as a reliable tool for neuropeptide discovery and peptide-based drug development. By providing a scalable and efficient deep learning framework, NeuroScale paves the way for future research in neuropeptide function, disease mechanisms, and therapeutic applications.</p>","PeriodicalId":9339,"journal":{"name":"BMC Biology","volume":"23 1","pages":"142"},"PeriodicalIF":4.4,"publicationDate":"2025-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12121104/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144172790","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Maternal genetic origin of Chao Lay coastal maritime populations from Thailand.","authors":"Wibhu Kutanan, Wipada Woravatin, Metawee Srikummool, Chatmongkon Suwannapoom, Alexander Hübner, Jatupol Kampuansai, Chawalit Khaokiew, Helmut Schaschl, Sanni Översti, Duy Duc La, Leonardo Arias, Mark Stoneking","doi":"10.1186/s12915-025-02252-5","DOIUrl":"10.1186/s12915-025-02252-5","url":null,"abstract":"<p><strong>Background: </strong>The Chao Lay, also known as sea nomads, include the Austronesian-speaking Moken, Moklen, and Urak Lawoi, who traditionally inhabit the coastal regions and islands of the Andaman Sea in southern Thailand. Their maritime lifestyle has attracted significant interest in their genetic origins and relationships with other sea nomad groups in Island Southeast Asia (ISEA); however, comprehensive genetic data on these communities remain scarce. Here, we generated complete mitochondrial genome sequences from Moken and Moklen groups, along with the Tai-Kadai-speaking southern Thai population and additional Austroasiatic-speaking Maniq samples (hunter-gatherer) from southern Thailand.</p><p><strong>Results: </strong>Our findings indicate that the Chao Lay display lower genetic diversity compared to the majority of southern Thai populations. Furthermore, the results suggest the absence of recent maternal expansions among the Chao Lay. Notably, haplogroups D4e1a, E1a1a1a, M21b2, M46a, M50a1, and M71c are predominant among the Chao Lay, underscoring their genetic distinctiveness. Bayesian coalescent age estimates of clades characteristic to Chao Lay for these haplogroups point to the time associated with the Austronesian expansion period.</p><p><strong>Conclusions: </strong>The Chao Lay populations were closer to each other than to other groups and exhibited more genetic connections to Mainland Southeast Asian (MSEA) populations than ISEA populations. However, we do not exclude potential origins of the Chao Lay in ISEA or Taiwan, as it is possible that ancestral Chao Lay males incorporated MSEA females into their communities upon arriving in Thailand. Further studies on genome-wide and Y chromosome data would provide more insights into their genetic history.</p>","PeriodicalId":9339,"journal":{"name":"BMC Biology","volume":"23 1","pages":"146"},"PeriodicalIF":4.4,"publicationDate":"2025-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12121263/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144172789","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"p53-mediated suppression of the SLC7 A11/GPX4 signaling pathway promotes trophoblast ferroptosis in preeclampsia.","authors":"Tingting Liao, Xia Xu, Guiying Wang, Jianying Yan","doi":"10.1186/s12915-025-02240-9","DOIUrl":"10.1186/s12915-025-02240-9","url":null,"abstract":"<p><strong>Background: </strong>Ferroptosis is an iron-dependent form of non-apoptotic cell death that occurs through increased plasma membrane phospholipid peroxidation in the context of impaired plasma membrane phospholipid peroxide repair systems. It has been reported that p53 can inhibit the expression of cysteine/glutamate reverse transporter solute carrier family 7, member 11 (SLC7A11), a key component of system Xc-, thus inhibiting cysteine uptake and promoting reactive oxygen species (ROS) accumulation as an important part of cell ferroptosis. Preeclampsia (PE) is an idiopathic hypertensive disease of pregnancy. Spiral artery insufficiency and impaired placental development are present at all stages, leading to placental hypoperfusion, ischemia, and hypoxia. However, the role of ferroptosis, particularly p53-mediated trophoblast ferroptosis, in placental dysfunction during PE remains unclear.</p><p><strong>Results: </strong>In PE placental tissues, malondialdehyde (MDA) and total iron levels were elevated, and trophoblasts exhibited typical ferroptosis-associated morphological changes. Additionally, p53 mRNA and protein expression and the percentage of p53-positive cells were increased, while SLC7A11 and GPX4 mRNA and protein expression and the percentage of positive cells were decreased. VEGFR1 protein expression was upregulated, whereas VEGFA and PLGF protein expression was downregulated. p53 protein expression was negatively correlated with the expression of proteins in the SLC7A11/GPX4 signaling pathway, VEGFA, and PLGF. Conversely, there was a positive correlation between p53 expression and MDA, total iron concentration, and VEGFR1. In vitro, the ferroptosis inducer erastin increased ROS levels in trophoblast cells. The ferroptosis inhibitor Fer-1, the apoptosis inhibitor Z-VAD-FMK, and the necrosis inhibitor Nec-1 failed to prevent erastin-induced ROS elevation. In p53 + / + trophoblasts, erastin-induced ROS elevation was more pronounced than that in p53 - / - and control cells, and angiogenesis was impaired. In pregnant rats, p53 + / + placentas exhibited increased MDA and total iron levels, ferroptosis-like morphological changes in trophoblasts, and reduced CD34 expression. p53 protein expression was negatively correlated with CD34 expression.</p><p><strong>Conclusion: </strong>This study confirmed that trophoblast ferroptosis occurs in the pathological state of PE and that trophoblast are specifically sensitive to ferroptosis. p53 can mediate the SLC7A11/GPX4 signaling pathway to promote ferroptosis of trophoblast cells in the pathogenesis of PE. It is also speculated that increased p53 reactivity may mediate impaired angiogenesis in placental tissues.</p>","PeriodicalId":9339,"journal":{"name":"BMC Biology","volume":"23 1","pages":"141"},"PeriodicalIF":4.4,"publicationDate":"2025-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12121027/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144172791","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"ER-plastid contact sites as molecular crossroads for plastid lipid biosynthesis.","authors":"Carolina Huercano, Miriam Moya-Barrientos, Oliver Cuevas, Victoria Sanchez-Vera, Noemi Ruiz-Lopez","doi":"10.1186/s12915-025-02239-2","DOIUrl":"10.1186/s12915-025-02239-2","url":null,"abstract":"<p><p>Membrane contact sites are specialized regions where organelle membranes are in close proximity, enabling lipid transfer while preserving membrane identity. In plants, ER‒chloroplast contact sites are critical for maintaining glycerolipid homeostasis. This review examines the lipid-modifying and lipid-transfer proteins/complexes involved in these processes. Key proteins at these sites, including components of the TGD and VAP27‒ORP2A complexes, as well as Sec14 proteins, facilitate lipid exchange. Additionally, the roles of lipid-modifying proteins at these contact sites are discussed. Despite significant progress, further research is needed to identify additional proteins, investigate ER‒chloroplast dynamics under stress and explore ER contact sites in non-chloroplast plastids.</p>","PeriodicalId":9339,"journal":{"name":"BMC Biology","volume":"23 1","pages":"139"},"PeriodicalIF":4.4,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12096540/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144126837","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Meiosis-associated expression patterns during starvation-induced cell fusion in the protist Fisculla terrestris.","authors":"Shan Gao, Marcel Dominik Solbach, Jens Bast, Kenneth Dumack","doi":"10.1186/s12915-025-02246-3","DOIUrl":"10.1186/s12915-025-02246-3","url":null,"abstract":"<p><strong>Background: </strong>Unicellular eukaryotes were widely considered to r eproduce without sex. However, recent findings suggest that meiosis, and by extension (sometimes cryptic) sexual reproduction, might be present in almost all eukaryotic lineages.</p><p><strong>Results: </strong>Here, we investigate the transcriptomic response underlying starvation-induced fusion in the Rhizaria protist Fisculla terrestris. Investigations of differentially expressed genes (DEGs) with a particular focus on the expression of meiosis-associated genes suggest that some form of meiosis and recombination might occur in these Rhizaria.</p><p><strong>Conclusions: </strong>We showed that starvation triggered changes in gene expression of meiosis-associated genes in F. terrestris. However, if these processes are coupled with sexual reproduction remains to be investigated.</p>","PeriodicalId":9339,"journal":{"name":"BMC Biology","volume":"23 1","pages":"140"},"PeriodicalIF":4.4,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12096724/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144126841","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Individual plant genetics reveal the control of local adaptation in European maize landraces.","authors":"Leke Victor Aiyesa, Dietrich Kaufmann, Birgit Zumbach, Wolfgang Link, Stefan Scholten, Timothy Beissinger","doi":"10.1186/s12915-025-02241-8","DOIUrl":"10.1186/s12915-025-02241-8","url":null,"abstract":"<p><strong>Background: </strong>European maize landraces encompass a large amount of genetic diversity, allowing them to be well-adapted to their local environments. This diversity can be exploited to improve the fitness of elite material in the face of a changing climate.</p><p><strong>Results: </strong>We characterized the genetic diversity of 333 individual plants from 40 European maize landrace populations (EMLPs). We identified five genetic groups that mirrored the proximities of their geographical origins. Fixation indices showed moderate differentiation among genetic groups (0.034 to 0.093). More than half of the genetic variance was observed to be partitioned among individuals. Nucleotide diversity of EMLPs decreased significantly as latitude increased (from 0.16 to 0.04), suggesting serial founder events during maize expansion in Europe. GWAS with latitude, longitude, and elevation as response variables identified 28, 347, and 68 significant SNP positions, respectively. We pinpointed significant SNPs near dwarf8, tb1, ZCN7, ZCN8, and ZmMADS69 and identified 126 candidate genes with ontology terms indicative of local adaptation in maize, regulating adaptation to diverse abiotic and biotic environmental stresses.</p><p><strong>Conclusions: </strong>This study suggests a quick and cost-efficient approach to identifying genes involved in local adaptation without requiring field data. The EMLPs used in this study have been assembled to serve as a continuing resource of genetic diversity for further research aimed at improving agronomically relevant adaptation traits.</p>","PeriodicalId":9339,"journal":{"name":"BMC Biology","volume":"23 1","pages":"138"},"PeriodicalIF":4.4,"publicationDate":"2025-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12096487/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144118801","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Horizontal cell connectivity in the anchovy retina-a 3D electron microscopic study.","authors":"Petra Guder, Max Scheungrab, Peter Kohnert, Georgios Kolyfetis, Gerhard Wanner, Martin Heß","doi":"10.1186/s12915-025-02242-7","DOIUrl":"10.1186/s12915-025-02242-7","url":null,"abstract":"<p><strong>Background: </strong>Block-face scanning electron microscopy has opened a new era of connectomics research, in which it is possible to make dense reconstructions of all cells in a clipping of a neuronal network, such as the retina, resolving synaptic contacts. Anchovies, exceptionally abundant marine teleosts, have retinae with regions for triple cone-based color vision and a region with specialized cone photoreceptors, so-called polycones, made of long and short cones with axially oriented outer segment lamellae for polarization contrast vision. This modality, discovered in the 1970s, is unique in vertebrates, but the neural wiring for contrast generation in deeper retinal layers is unknown so far.</p><p><strong>Results: </strong>To elucidate the retinal connectomics of the European anchovy Engraulis encrasicolus (Linnaeus, 1758), in a first project, we investigated the shapes and cone-specific wiring rules of 3 horizontal cell types using volume electron microscopy and subsequent computer-aided reconstruction: H1 cells contact both cone types of the polycone, H2 cells contact only the short cones, and H3 cells are exclusively connected to rods. In addition, a distinctive double band of Müller fibers and a layer of H1 axon terminals were structurally clarified.</p><p><strong>Conclusions: </strong>The findings suggest that (1) the monochromatic polarization contrast system based on fine structure specializations in the outer retina is connected to an inherited (bichromatic) color contrast mechanism in the inner retina, (2) the anchovy polycones arose from red (now long) and green (now short) cones, and (3) the blue single cones disappeared in the relevant retinal region.</p>","PeriodicalId":9339,"journal":{"name":"BMC Biology","volume":"23 1","pages":"137"},"PeriodicalIF":4.4,"publicationDate":"2025-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12090589/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144101433","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}