Protoplasma最新文献

{"title":"Ontogenesis of the anastomosed laticifers of Allamanda cathartica (Apocynaceae) and the chemical nature of the stem latex.","authors":"Maria Gabriela Ferreira Figueiredo, Leonardo Monteiro Ribeiro, Maria Olívia Mercadante-Simões","doi":"10.1007/s00709-024-01999-y","DOIUrl":"10.1007/s00709-024-01999-y","url":null,"abstract":"<p><p>Laticifers are secretive structures with important roles in controlling abiotic and biotic stress through the external release of viscous and bioactive latex emulsions composed of alkaloids, terpenes, flavonoids, proteins, and mucilage. Allamanda cathartica is an attractive ornamental neotropical shrub that produces abundant latex with medicinal potential. The laticifers of this species, their origins, structural types, and distribution in the primary and secondary structures of the stem were investigated, and the chemical nature of latex was determined. Anatomical, histochemical, and ultrastructural evaluations of the stem apex were performed through light and electronic microscopy. Laticifers are abundant in the primary structure, being distributed in the cortex, outer primary phloem, and pith. Their branching, anastomosing structural type develops by the dissolution of the transverse and lateral walls of precursor meristematic cells, followed by protoplast fusion. The laticifers in the secondary structure are distributed amid the axial parenchyma cells of the phloem. The latex of A. cathartica is an emulsion composed mainly of mucilage and terpenes, and it is the first time that this laticifer system has been described.</p>","PeriodicalId":20731,"journal":{"name":"Protoplasma","volume":" ","pages":"353-363"},"PeriodicalIF":2.5,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142473223","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Double defense: chemical and mechanical protection of the vegetative apices of Begonia curtii (Begoniaceae)-an endemic species of the Atlantic forest.","authors":"Marco Aurélio Batista, Dayana Maria Teodoro Francino, Valdnéa Casagrande Dalvi","doi":"10.1007/s00709-025-02046-0","DOIUrl":"https://doi.org/10.1007/s00709-025-02046-0","url":null,"abstract":"<p><p>The stem apical meristems (SAM) are essential for the primary growth of plants and possess protective mechanisms to safeguard their fragile structures, including stipules and chemical secretions such as mucilage. This study examines Begonia curtii, focusing on the origin and composition of its protective sticky secretions. The research is set within the Atlantic Forest-a biodiversity hotspot-highlighting the plant's adaptive survival strategies. Samples of leaves and stipules at three stages of development were collected and analyzed using micromorphological, anatomical and histochemical techniques. The stem apices of B. curtii are covered by large, green stipules, which protect developing leaves and stipules with a mucilaginous secretion produced by trichomes and idioblasts present in both organs. Mucilage, originating from idioblasts present in the stipules, accumulates in the substomatal chambers and is released by the stomata, an atypical phenomena. The exudate from the hydathodes increases the volume of secretion to hydrate young organs and meristematic regions, protecting them from desiccation. The adult stipules remain attached to the stem, become dry, and without secretions, while the multiple epidermis and idioblasts, in adult leaves, store water and mucilage, respectively. The morphological and chemical differences between the leaves and stipules of B. curtii at different stages of development, reinforce both their physical and chemical protective roles in the face of biotic and abiotic factors typical of the Atlantic Forest's rocky outcrops.</p>","PeriodicalId":20731,"journal":{"name":"Protoplasma","volume":" ","pages":""},"PeriodicalIF":2.5,"publicationDate":"2025-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143472936","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Structural characteristics of leaf trichomes and epidermis in species from three sections of the genus Aristolochia.","authors":"O V Nakonechnaya, Yu A Khrolenko, A V Kalachev, V M Kazarin, T Y Gorpenchenko","doi":"10.1007/s00709-025-02045-1","DOIUrl":"https://doi.org/10.1007/s00709-025-02045-1","url":null,"abstract":"<p><p>The structure of leaf epidermis in species from three sections (Diplolobus, Gymnolobus, and Siphisia) of the genus Aristolochia has been examined by light and scanning microscopy methods. As the results show, the number of the stomata and the length of stomatal guard cells in plants growing ex situ are not related to habitat conditions but are probably determined genetically. According to the type of leaf epicuticular waxes, the studied taxa can be divided into three groups, of which the Aristolochia-type is the most common. This type is characteristic of all studied species of the section Siphisia. The presence of two types of trichomes in members of this section distinguishes them from the other sections. Representatives of the sections with the Convallaria-type wax lack trichomes. The noted differences allow accurate identification of each of the species in the genus. The features of the epidermis surface, types and arrangement of stomata, and types of trichomes are additional diagnostic characteristics useful for taxonomy.</p>","PeriodicalId":20731,"journal":{"name":"Protoplasma","volume":" ","pages":""},"PeriodicalIF":2.5,"publicationDate":"2025-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143449958","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An immunohistochemical approach to cell wall polysaccharide specialization in maritime pine (Pinus pinaster) needles.","authors":"Santiago Michavila, Antonio Encina, Alfonso G De la Rubia, María Luz Centeno, Penélope García-Angulo","doi":"10.1007/s00709-025-02041-5","DOIUrl":"https://doi.org/10.1007/s00709-025-02041-5","url":null,"abstract":"<p><p>Pine needles are specialized leaves bearing distinctive anatomical features whose function is to minimize water loss. At the molecular level, needle specialization is expected to lead to heterogeneity in cell wall (CW) composition. By immunohistochemical analysis of CW epitopes in maritime pine (Pinus pinaster) needles, we described the variability of CW composition in all tissues, discussing its possible relationship with the cell function. Cells specialized in water transport, tracheids, transfusion tracheids, and endodermis, together with epi/hypodermal and stomatal cells, had similar CW composition, where epitopes for pectins (homogalacturonan and rhamnogalacturonan-I), xyloglucan, and heteroxylans were abundant. Heteroxylans differ between the dermis, enriched in arabinoxylan, and endodermis, enriched in glucuronoxylan. Xylem CWs were very rich in (arabino)xylans and homogalacturonan and distinctively lacked immunolabelling for rhamnogalacturonan-I. CWs from phloem, transfusion phloem, mesophyll, and resin ducts were enriched in homogalacturonan, rhamnogalacturonan-I, and xyloglucan, showing a low content for heteroxylan epitopes. Arabinogalactan proteins were detected in mesophyll and in cells specialized in solute transport such as phloem, duct sheath, and guard cells. These results show that tissues with similar functions have similar polysaccharide composition, shedding light on the role of CW components through different tissues.</p>","PeriodicalId":20731,"journal":{"name":"Protoplasma","volume":" ","pages":""},"PeriodicalIF":2.5,"publicationDate":"2025-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143441803","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Morphological development of the endosperm epidermal cells in waxy wheat cultivars.","authors":"Juan Liu, Yuangang Zhu, Xinyue Liu, Jian Song, Ligang Tang, Liang Shen, Zhongmin Dai","doi":"10.1007/s00709-025-02034-4","DOIUrl":"https://doi.org/10.1007/s00709-025-02034-4","url":null,"abstract":"<p><p>Endosperm epidermal cells (EECs) accumulate large quantities of nutrients; they also play key roles in facilitating solute transport. Comprehensive knowledge about the dynamic development of EECs is needed to understand the relationship between their dual functions. In this study, the developmental characteristics of EECs in wheat grains of two near-isogenic lines (Shimai19-P and Shimai19-N) and in the parent wheat cultivar Shimai19 were compared using light and scanning electron microscopy. The intermediate EECs located adjacent to the nucellar projection (NP) on the ventral surface of wheat grains rapidly differentiated. Eight days after pollination (8 DAP), these EECs were larger in Shimai19-N than in the other wheat cultivars; they had differentiated into endosperm transfer cells (ETCs). At 14 DAP, the number of ETCs reached a maximum and then gradually decreased in all three wheat varieties. The lateral ETCs and the ETCs on both sides of the crease were longer than ACs; they reached their maximum length at 16 DAP, becoming gradually shorter thereafter. The dorsal ACs became increasingly thicker during wheat grain development. Overall, these results suggested that EECs near the EC and crease are important for efficient nutrient transport, whereas EECs in other regions of wheat grains mainly play a role in nutrient storage.</p>","PeriodicalId":20731,"journal":{"name":"Protoplasma","volume":" ","pages":""},"PeriodicalIF":2.5,"publicationDate":"2025-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143426031","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ethylene response factors as potential regulators of cell wall formation in celery (Apium graveolens L.) collenchyma: phylogeny and gene expression analysis.","authors":"Natalya Syrchina, Polina Mikshina, Natalia Mokshina","doi":"10.1007/s00709-025-02042-4","DOIUrl":"https://doi.org/10.1007/s00709-025-02042-4","url":null,"abstract":"<p><p>Collenchyma is a mechanical tissue characterized by cells that can elongate despite having thickened cell walls. This ability to elongate, along with the biochemical composition of the collenchyma cell wall, allows it to be referred to as the primary cell wall (PCW). However, the regulation of PCW biosynthesis, even at the master switch level, remains a stumbling block for cell wall biologists. While only a few members of the IIId and IIIe phylogenetic subgroups of ethylene response factors (ERFs) have been identified as regulators of PCW formation, an analysis of the differential expression of AgrERFs was conducted to uncover potential regulators involved in collenchyma cell wall formation. Additionally, we performed a phylogenetic analysis of celery AgrERFs for comprehensive revision and annotation. A separate effort was dedicated to identifying reference genes for celery, utilizing the quantitative real-time PCR technique. The most stably expressed genes, TIP41 and CACTIN, were selected as reference genes for this species. Transcriptome profiling of celery petiole tissues revealed a group of AgrERFs that are highly and specifically expressed in collenchyma during petiole growth. Among these, AgrERF002b, AgrERF041b, and AgrERF079 had the highest correlation coefficients of coexpression with genes encoding cell wall-related proteins, including cellulose synthases involved in PCW biosynthesis (AgrCESA1, 3, and 6). This suggests a potential role of these transcription factors in regulating PCW biosynthesis. Furthermore, AgrERF039, a member of the IIId group, along with several other AgrERFs, was coexpressed with genes encoding secondary cell wall-related cellulose synthases (AgrCESA4, 7, and 8).</p>","PeriodicalId":20731,"journal":{"name":"Protoplasma","volume":" ","pages":""},"PeriodicalIF":2.5,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143391565","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microscopic and ultrastructural observations on the regenerating scales of the lizard Podarcis muralis clarify the origin of the micro-ornamentation.","authors":"A Bonfitto, R Randi, M Ciubotaru, L Alibardi","doi":"10.1007/s00709-025-02040-6","DOIUrl":"https://doi.org/10.1007/s00709-025-02040-6","url":null,"abstract":"<p><p>The present study conducted using immunofluorescence, scanning electron microscopy, and transmission electron microscopy aims to determine the origin of the lamellated pattern and of the micro-ornamentation formed in tail scales of the lacertid lizard Podarcis muralis. Regenerating scales shows the typical formation of all the epidermal layers of lizard epidermis, including clear and Oberhautchen layers. The latter initiates the accumulation of hard corneous material containing corneous beta proteins (CBPs) that determine a tension with the overlaying softer clear layer containing mainly intermediate filaments of keratins (IFKs). The two layers, initially joined by numerous desmosomes, are later displaced one from the other with the growth of regenerating scales, forming a slanted surface as observed under transmission electron microscopy (TEM). At the beginning of scale regeneration, the slanted tips form an irregular lamellated pattern on the surface of Oberhautchen cells, appearing as crests or waves under scanning electron microscopy (SEM). In the following scale differentiation, growth, and shedding of molt, the irregular crests form a more ordered and parallel microsculptured and micro-ornamentation pattern when Oberhautchen and beta-cells merge one to another and give rise to a mature beta-layer. Hard CBP-based corneous material and electron-dense materials of unknown composition together with IFKs are accumulated in the slanted surface of the differentiating Oberhautchen cells. During scale growth, the Oberhautchen surface matures into a jig-saw outline that gives rise to the lamellated pattern of mature micro-ornamentation. The study suggests that complex micro-ornamentation patterns in other lizard species can also vary during scale formation, in development, growth, or regeneration.</p>","PeriodicalId":20731,"journal":{"name":"Protoplasma","volume":" ","pages":""},"PeriodicalIF":2.5,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143382516","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cerium oxide nanoparticles ameliorate Arabidopsis thaliana root damage under UV-B stress by modulating the cell cycle and auxin pathways.","authors":"Cheng Sun, Chen Zhao, Guohua Wang, Rong Han","doi":"10.1007/s00709-025-02038-0","DOIUrl":"https://doi.org/10.1007/s00709-025-02038-0","url":null,"abstract":"<p><p>Cerium oxide nanoparticles (CeO₂-NPs) have been widely applied worldwide. In the field of agriculture, they have gained attention for their ability to promote seed germination, root elongation, and biomass accumulation in plants, as well as to increase plant resistance to various abiotic stresses. However, the underlying molecular mechanisms remain to be elucidated. Limited research has been conducted on whether CeO₂-NPs can help plants mitigate damage caused by UV-B stress. In this study, Arabidopsis thaliana was selected as the research subject to investigate the effects of CeO₂-NPs on the resistance of plant roots to UV-B stress at both the physiological and molecular levels. Our findings demonstrated that 120 mg/mL CeO₂-NPs significantly alleviated UV-B-induced damage to the root system of Arabidopsis thaliana. Specifically, CeO₂-NPs increased the activities of the root tip antioxidant enzymes superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT), reducing oxidative stress. The results from GUS staining and GFP fluorescence assays conducted on the transgenic lines CYCB1;1-GUS, DR5-GUS, QC25-GUS, and WOX5-GFP indicated that CeO₂-NPs could increase the cell division activity, auxin accumulation, and stem cell niche activity of Arabidopsis thaliana root tips under UV-B stress. Furthermore, observations of GFP fluorescence in the transgenic lines PIN1-GFP, PIN2-GFP, and PIN7-GFP revealed that CeO₂-NPs promoted root growth by inducing the accumulation of auxin transporters. Quantitative real-time PCR (qRT-PCR) analysis revealed that under UV-B stress, CeO₂-NPs upregulated the expression of genes related to antioxidant enzymes, the cell cycle and auxin biosynthesis-related genes in Arabidopsis thaliana root tips while downregulating the expression of genes related to DNA damage repair and stress response. Therefore, CeO₂-NPs have potential value for promoting plant growth and mitigating UV-B stress.</p>","PeriodicalId":20731,"journal":{"name":"Protoplasma","volume":" ","pages":""},"PeriodicalIF":2.5,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143190219","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"TGG1 and TGG2 mutations impair allyl isothiocyanate-mediated stomatal closure in Arabidopsis thaliana.","authors":"Kadri Oumaima, Mohammad Shakhawat Hossain, Wenxiu Ye, Eiji Okuma, Mohammad Issak, Mohammad Mahbub Islam, Misugi Uraji, Yoshimasa Nakamura, Izumi C Mori, Shintaro Munemasa, Yoshiyuki Murata","doi":"10.1007/s00709-025-02039-z","DOIUrl":"https://doi.org/10.1007/s00709-025-02039-z","url":null,"abstract":"<p><p>Myrosinase, referred to as thioglucoside glucohydrolase (TGG), plays a crucial role in plant physiology through catalyzing the hydrolysis of glucosinolates into bioactive isothiocyanates. In Arabidopsis thaliana, the myrosinases TGG1 and TGG2 are essential for abscisic acid- and methyl jasmonate-induced stomata closure. Allyl isothiocyanate (AITC), one of myrosinase products, triggers stomatal closure in A. thaliana. We investigated stomatal responses to AITC to clarify the role of TGG1 and TGG2 in Arabidopsis guard-cell signaling. Allyl isothiocyanate at 50 μM and 100 μM induced stomatal closure in the tgg1 and tgg2 single mutants but not in the tgg1 tgg2 double mutant. Furthermore, AITC at 50 μM induced the production of reactive oxygen species and nitric oxide, cytosolic alkalization, and oscillations in cytosolic free calcium concentration in guard cells of both wild-type and mutant plants. These findings suggest that TGG1 and TGG2 are involved in AITC signaling pathway through interaction with signal component(s) downstream of these signaling events, which is not accompanied by hydrolysis of glucosinolates because of the difference in subcellular localization between enzymes (myrosinases) and substrates (glucosinolates).</p>","PeriodicalId":20731,"journal":{"name":"Protoplasma","volume":" ","pages":""},"PeriodicalIF":2.5,"publicationDate":"2025-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143080751","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of Ty3/gypsy and Ty1/copia LTR-retrotransposons on the large genomes of Alstroemeriaceae: genome landscape of Bomarea edulis (Tussac) Herb.","authors":"Jéssica Nascimento, Mariela Sader, Tiago Ribeiro, Andrea Pedrosa-Harand","doi":"10.1007/s00709-025-02036-2","DOIUrl":"https://doi.org/10.1007/s00709-025-02036-2","url":null,"abstract":"<p><p>Repetitive elements are the main components of many plant genomes and play a crucial role in the variation of genome size and structure, ultimately impacting species diversification and adaptation. Alstroemeriaceae exhibits species with large genomes, not attributed to polyploidy. In this study, we analysed the repetitive fraction of the genome of Bomarea edulis through low-coverage sequencing and in silico characterization, and compared it to the repeats of Alstroemeria longistaminea, a species from a sister genus that has been previously characterized. LTR-retrotransposons were identified as the most abundant elements in the B. edulis genome (50.22%), with significant variations in abundance for specific lineages between the two species. The expansion of the B. edulis genome was likely due to three main lineages of LTR retrotransposons, Ty3/gypsy Tekay and Retand and Ty1/copia SIRE, all represented by truncated elements which were probably active in the past. Furthermore, the proportion of satDNA (~ 7%) was six times higher in B. edulis compared to A. longistaminea, with most families exhibiting a dispersed, uniform distribution in the genome. SatDNAs, thus, contributed to some extent to genome obesity. Despite diverging around 29 Mya, both species still share some satDNA families and retrotransposons. However, differences in repeat abundances and sequence variants led to genome differentiation despite their similar sizes and structure.</p>","PeriodicalId":20731,"journal":{"name":"Protoplasma","volume":" ","pages":""},"PeriodicalIF":2.5,"publicationDate":"2025-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143067523","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}