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1.
The sperm ultrastructure of the short‐faced scorpionfly Panorpodes kuandianensis Zhong et al. was investigated using transmission electron microscopy. The spermatozoon is composed of a short head containing a bilayered acrosome and an elongate nucleus, a neck transition region, and a long flagellum. The acrosome consists of an acrosomal vesicle and a central perforatorium. The nucleus has two deep, U‐shaped lateral grooves and its chromatin contains a series of parallel, regularly arrayed nuclear fibers. The barrel‐shaped centriolar adjunct occupies the most volume of the neck region. The flagellum is helical for its whole length and is formed by an axoneme, two mitochondrial derivatives, a pair of accessory bodies, and peculiar accessory structures. The axoneme has nine accessory microtubules at the anterior flagellum region, displaying a 9 + 9 + 2 microtubular pattern, but the accessory microtubules are short and disappear quickly. The two mitochondrial derivatives differ in length and diameter. In the more posterior region, the remaining anchor‐shaped mitochondrial derivative has a circular crystalline region, differing from other mecopteran species. The filiform materials are peculiar and lie beside the nucleus and in the flagellum region. Sperm ultrastructural comparison of P. kuandianensis with other families supports a close affinity of Panorpodidae with Panorpidae. In addition, the occurrence of the nine accessory microtubules in the sperm axoneme of Panorpodes indicates that the 9 + 9 + 2 axonemal pattern might be a symplesiomorphy of the Mecoptera. Microsc. Res. Tech. 77:394–400, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   

2.
In Digelasinus diversipes, spermatozoa are maintained in bundles, with 74 spermatozoa on average, in the seminal vesicle. These spermatozoa are very short (20 μm) and consist of a head and flagellum. The head includes an acrosome (perforatorium covered by the acrosomal vesicle) and a nucleus. A regular electron-lucent region separates the acrosomal vesicle from the perforatorium, which is inserted parallel to the anterior ending of the nucleus. The small flagellum is composed of two symmetrical mitochondrial derivatives, a centriolar adjunct, an axoneme (9 + 9 + 2), and two accessory bodies. The centriolar adjunct begins above the posterior end of the nucleus and ends covering the anterior tip of two mitochondrial derivatives. In the terminal region of the axoneme, the central microtubules terminate first. The presence of a subacrosomal space, a short mitochondrial derivative diameter, and a short spermatodesm is the ultrastructure characteristics of spermatozoa shared by all "symphyta" species. Differences in the insertion of the perforatorium into the nucleus and the position of the centriolar adjunct distinguish Dielocerinae and the Arginae studied previously. The number of spermatozoa per cyst is variable. Furthermore, additional characteristics that had not been described for "symphyta" were also found, such as the number of follicles per testis.  相似文献   

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Morphology of spermatozoa in bees has provided promising results for phylogenetic analyses. In this work, the structure and ultrastructure of spermatozoa from Thygater (Thygater) analis and Melitoma segmentaria were characterized and the synapomorphies shared in the family Apidae are discussed. In these species, spermatozoa bundles which are undone in the seminal vesicle possess, on average, 50 cells. Spermatozoa consist of a head and a flagellar region. The head includes an acrosome containing the perforatorium, covered by the acrosomal vesicle and a nucleus. The flagellum is formed by two mitochondrial derivatives, which are asymmetric in diameter and length, with one centriolar adjunct, one axoneme (9 + 9 + 2), and two accessory bodies. In cross section the centriolar adjunct is asymmetric and the accessory bodies are triangular in shape. In the distal region of the flagellum, the derivative terminates before the axoneme and the small derivative terminates first. The axoneme is gradually disorganized and the accessories microtubules are the last to terminate. In these two species, spermatozoa share diverse synapomorphies with those of other bee species previously described in the literature, which allows for the establishment of a morphological pattern for spermatozoa of the family Apidae.  相似文献   

4.
The spermatogenesis of Piaractus mesopotamicus was investigated under light and transmission electron microscopy. The specimens were captured from their natural environment (Rio Miranda and Rio Aquidauana, Pantanal Matogrossense, Brazil) during April and September. The results were compared with the spermatogenic data of specimens under captivity condition. In both conditions, P. mesopotamicus presented the typical spermatogenesis pattern of the teleost fishes, showing no significative differences. The spermatozoon was classified as type I, which has a globular head without acrosome, a short middle piece and a long tail constituted only by the flagellum. This type of spermatozoon is considered the basic type in fishes.  相似文献   

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Ultrastructural analyses of bivalve spermatozoa are relevant in studies that aim to identify taxonomic traits for the purposes of discriminating species and conducting phylogenetic studies. In the present work, spermatozoa of mussel specimens of the genus Mytella, collected from two populations living in distinct habitats, were examined by electron microscopy. The objective was to identify sperm ultrastructural taxonomic traits that could be used to differentiate Mytella species. The specimens were from populations that live in intertidal zones on the southeast coast of Brazil, either buried in muddy-sand sediment or anchored to rocky substrates. The acrosomal vesicle was conical and long, the axial rod extended from the nucleus to the acrosome, the nucleus was an oblate spheroid with a condensed chromatin, the intermediate portion contained mitochondria encircling a pair of centrioles, and there was a single flagellum. The sperm was of a primitive type. The spermatozoon ultrastructure did not distinguish the specimens buried in muddy-sand sediment from those anchored to rocky substrates. The data suggest that the specimens analyzed, despite living in distinct habitats, belong to the same species, which conchological analyses identified as M. charruana. The presence of an axial rod in their sperm cells supports the inclusion of M. charruana in the subfamily Mytilinae.  相似文献   

9.
Broussonetia kazinoki × Broussonetia papyrifera (ZJGS) is a hybrid species in Moraceae family, which has a very complicated hybrid origin. The excellent characteristics of fast growth, strong soil and water conservation ability, high leaf protein content and stem fiber content in ZJGS make it both ecological benefits in the mining area and economically valuable. This study aims to further understand ZJGS and other Moraceae taxa through the ZJGS chloroplast (cp) genome structure and the comparison with 12 closely related Moraceae species. Among the 13 Moraceae species, the cp genome length of seven Broussonetia species (ranges from 160,239 bp to 162,594 bp) is larger than that of six Morus species (ranges from 158,459 bp to 159,265 bp). Among the 77 shared protein-coding genes (PCGs) in Moraceae species, the obvious positive selection of Ka/Ks ratios acted on petD and rpl16 genes of B. kazinoki and B. papyrifera, respectively. Phylogenetic analysis based on shared PCGs from 28 species shows that ZJGS is closely related to maternal B. kazinoki. These findings provide data support for the origin of ZJGS hybridization and provide genomic resources for future ZJGS resource development and molecular breeding.  相似文献   

10.
Observation of sperm development and determination of their morphological characteristics are very important to the understanding of phylogenetic relationships and the study of sperm function during fertilization. Although ultrastructural studies of sperm development in the testes of the fruit fly Drosophila have been performed, there are few reports describing electron microscopic morphology of mature sperm, that is, those released from the testes to the seminal vesicles. Here, we present the first report of the sagittal organization of Drosophila sperm head and neck regions by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The head and tail structures of a mature sperm, for example, the acrosome, nucleus, and flagellum, were easy to distinguish by the morphological characteristics of the sperm surface by SEM. The morphological relationships between the surface and internal structures of mature sperm were confirmed by observing longitudinal sections with TEM. Our approach overcame the technical difficulties involved in sample preparation for electron microscopic observation of the Drosophila mature sperm head, and therefore, this study serves as an important foundation for future genetic dissection of sperm ultrastructure and function in male sterile mutants. Microsc. Res. Tech. 77:661–666, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   

11.
The term “undruggable” is to describe molecules that are not targetable or at least hard to target pharmacologically. Unfortunately, some targets with potent oncogenic activity fall into this category, and currently little is known about how to solve this problem, which largely hampered drug research on human cancers. Ras, as one of the most common oncogenes, was previously considered “undruggable”, but in recent years, a few small molecules like Sotorasib (AMG-510) have emerged and proved their targeted anti-cancer effects. Further, myc, as one of the most studied oncogenes, and tp53, being the most common tumor suppressor genes, are both considered “undruggable”. Many attempts have been made to target these “undruggable” targets, but little progress has been made yet. This article summarizes the current progress of direct and indirect targeting approaches for ras, myc, two oncogenes, and tp53, a tumor suppressor gene. These are potential therapeutic targets but are considered “undruggable”. We conclude with some emerging research approaches like proteolysis targeting chimeras (PROTACs), cancer vaccines, and artificial intelligence (AI)-based drug discovery, which might provide new cues for cancer intervention. Therefore, this review sets out to clarify the current status of targeted anti-cancer drug research, and the insights gained from this review may be of assistance to learn from experience and find new ideas in developing new chemicals that directly target such “undruggable” molecules.  相似文献   

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Somatic embryogenesis is an asexual reproduction process that occurs in many plant species, including rice. This process contains several totipotency markers such as Somatic Embryogenesis Receptor-like Kinase (SERK), Leafy Cotyledon1 (LEC1) and WUSCHEL-Related Homeobox4 (WOX4) and also a helpful model for embryo development and clones and transformations. Here, we report the gene expression during somatic embryo development correlates with regeneration frequency in 14 Javanica rice (pigmented and non-pigmented) using modifified N6 media supplemented with Kinetin (2.0 mg/L) and NAA (1.0 mg/L). Although there have been advances in understanding the genetic basis of somatic embryogenesis in other varieties, rice is still unexplored, especially during somatic embryo development. Moreover, for the formation of callus induction from immature embryos, 2,4-D (2.0 mg/L, 3.0 mg/L) was used. This study analysed the gene expression of OsSERK, OsWOX4 and OsLEC1 genes through RT-PCR analysis. Higher expression of the OsLEC1 gene indicates that their function may correlate in the in vitro with the high response of rice after transfer to regeneration media. This study found that rice varieties of pigmented rice (MS Pendek and Gogoniti II) and non-pigmented rice (Pandan Ungu) showed high regeneration frequency, showing higher OsLEC1 expression than other varieties because OsLEC1 promotes the maturation of somatic embryos in plant regeneration on day 14. However, the contrast with Genjah nganjuk may be effective because of other regulatory genes. RT-PCR analysis showed OsSERK had less expression level than OsLEC1 and OsWOX4 in the varieties, which correlate with the percentage of plant regeneration, but not for Gogoniti II. In conclusion, the higher percentage of plant regeneration correlates with the higher expression level of OsLEC1 at day 14 of media regeneration of rice.  相似文献   

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Background: Inflammatory bowel disease (IBD) is a chronic inflammatory disease of the gastrointestinal tract. The destruction of the intestinal epithelial barrier is one of the major pathological processes in IBD pathology. Growing evidence indicated that epithelial cell ferroptosis is linked to IBD and is considered a target process. Methods: RAS-selective lethal 3 (RSL3) was used to induce ferroptosis in intestinal epithelial cell line No. 6 (IEC-6) cells, and cell ferroptosis and the effects of tanshinone IIA (Tan IIA) were determined by cell counting kit-8 (CCK-8), reactive oxygen species (ROS) staining, Giemsa staining and transmission electron microscope (TEM). The cell viability of natural product library compounds was determined by CCK-8. The expression of ferroptosis-related genes were detected by real-time quantitative polymerase chain reaction (RT-qPCR) and western blot. Results: Treatment of IEC-6 cells results in the accumulation of ROS and typical morphological characteristics of ferroptosis. RSL3 treatment caused rapid cellular cytotoxicity which could be reversed by ferrostatin-1 (Fer-1) in IEC-6 cells. Natural product library screening revealed that Tan IIA is a potent inhibitor of IEC-6 cell ferroptosis. Tan IIA could significantly protect the RSL3-induced ferroptosis of IEC-6 cells. Furthermore, the ferroptosis suppressors, glutathione peroxidase 4 (GPX4), solute carrier family 7 member 11 (SLC7A11), and miR-17-92 were found to be early response genes in RSL3-treated cells. Treatment of IEC-6 cells with Tan IIA resulted in upregulation of GPX4, SLC7A11, and miR-17-92. Conclusion: Our study demonstrated that Tan IIA protects IEC-6 cells from ferroptosis through the upregulation of GPX4, SLC7A11, and miR-17-92. The findings might provide a theoretical grounding for the future application of Tan IIA to treat or prevent IBD.  相似文献   

15.
Randomly amplified polymorphic DNA (RAPD) is a tremendously convenient approach used to discriminate between Brassica species owing to its accuracy and speed. RAPD primers generate adequate genetic information that can be used in the primer-marker system. In this work, twenty RAPD-PCR based markers were executed to generate polymorphic data, like polymorphic information content (PIC), mean resolving power (MRP), resolving power (RP), effective multiplex ratio (EMR), and marker index (MI) for the first time and genetic distance among and between six Brassica species were calculated. Our results indicated that 20 primers produced a total of 231 scored band and generated 87% polymorphic bands. Average PIC, MRP, RP, MI, and EMR values were 0.088, 0.65, 6.7, 0.78, and 8.9, respectively. PIC showed an overall negative correlation with MRP, RP, MI, and EMR, whereas MRP, RP, and EMR, were positively correlated with each other. Genetic identities ranged from 41.99% (between Brassica napus and Brassica oleracea) to 68.83% (between Brassica campestris and Brassica oleracea). Dendrogram results showed no clustering between species except between Brassica campestris and Brassica nigra. Nevertheless, these results will be helpful to acquire useful information about the markers and their use to determine the genomic structures of Brassica species. Further, based on genetic distance and polymorphic information, new hybrids can be developed for effective oilseed production.  相似文献   

16.
Azalea is a general designation of Rhododendron in the Ericaceae family. Rhododendron not only has high ornamental value but also has application value in ecological protection, medicine, and scientific research. In this study, we used Illumina and PacBio sequencing to assemble and annotate the entire chloroplast genomes (cp genomes) of four Rhododendron species. The chloroplast genomes of R. concinnum, R. henanense subsp. lingbaoense, R. micranthum, and R. simsii were assembled into 207,236, 208,015, 207,233, and 206,912 bp, respectively. All chloroplast genomes contain eight rRNA genes, with either 88 or 89 protein-coding genes. The four cp genomes were compared and analyzed by bioinformatics, and the phylogenetic analysis based on chloroplast genomes of 26 species of Ericaceae, Actinidiaceae, and Primulaceae under Ericales was conducted. A comparison of the linear structure of cp genomes of four Rhododendron showed that there were substantial sequence similarities in coding regions, but high differences in non-coding regions. A phylogenetic analysis, based on chloroplast whole genome sequences, showed that all Rhododendron species are in the clade Ericaceae. This study provides valuable genetic information for the study of population genetics and evolutionary relationships in Rhododendron and other azalea species.  相似文献   

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Clubroot of Chinese cabbage (Brassica rapa L. ssp. pekinensis), caused by the obligate parasite Plasmodiophora brassicae, accounts for serious yield losses. The aim of our study was to explore the phytohormone levels and metabolome changes in the roots of resistant and susceptible B. rapa genotypes at a late stage of infection, i.e., 28 days post-infection. Both genotypes showed decreased auxin levels after P. brassicae infection except for indole-3-acetic acid. Overall, the susceptible genotype had higher auxin and cytokinin levels after infection, with the exception of trans-zeatin and 3- indolebutyric acid as compared to the resistant genotype. Jasmonic acid levels declined after infection regardless of the genotype. Resistance against clubroot was evident with the increased levels of salicylic acid in the resistant genotype. The susceptible genotype had a higher number of differentially accumulated metabolites (DAMs) (262) than the resistant genotype (238) after infection. Interestingly, 132 DAMs were commonly detected in both genotypes when infected with the pathogen, belonging to metabolite classes such as phenolic acids, amino acids, and derivatives, glucosinolates, organic acids, flavonoids, nucleotides and derivatives, and fatty acids. The differential metabolite analysis revealed that metabolites related to amino acid biosynthesis, fatty acid biosynthesis and elongation, glutathione metabolism, and glucosinolate metabolism were highly accumulated in the resistant genotype, suggesting their essential roles in resistance against P. brassicae infection.  相似文献   

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Plant U-box (PUB) E3 ubiquitin ligases play important roles in hormone signaling pathways and in response to different abiotic stresses, but little is known about U-box genes in Danshen (root of Salvia miltiorrhiza Bunge). Here, we identified and characterized 70 SmPUB genes based on its genome sequence. Phylogenetic analysis of U-box genes from S. miltiorrhiza and Arabidopsis suggested that they can be clustered into seven subgroups (I–VII). Typical U-box domains were found in all identified SmPUB genes through the analysis of conserved motifs. Moreover, qRT-PCR was applied to analyze the relative expression levels of U-box genes in S. miltiorrhiza roots and leaves under PEG-induced water deficit and salt stresses. Results revealed that the SmPUB genes exhibited stronger response to drought than to salt stress. To the best of our knowledge, this report is the first to perform genome-wide identification and analysis of the U-box gene family in S. miltiorrhiza, and the results provide valuable information for better understanding of the function of U-box in S. miltiorrhiza.  相似文献   

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Background: Colon adenocarcinoma (COAD) is the second leading cause of cancer death worldwide thus, identification of COAD biomarkers is critical. Mitotic Arrest Deficient 2 Like 2 (MAD2L2) is a key factor in mammalian DNA damage repair and is highly expressed in many malignant tumors. This is a comprehensive study of MAD2L2 expression, its diagnostic value, prognostic analysis, potential biological function, and impact on the immune system of patients with COAD. Methods: Gene expression, clinical relevance, prognostic analysis, diagnostic value, GO/KEGG cluster analysis, data obtained from TCGA, and bioinformatics statistical analysis were performed using the R package. Immune responses to MAD2L2 expression in COAD were analyzed using TIMER. The expression of MAD2L2 in HCT116 cells induced by the inflammatory factor TNF-α was detected using Western blot. Results: Our results underscore the clinical diagnostic value and potential biological significance of MAD2L2 in patients with COAD. A high level of MAD2L2 expression has been found in COAD and correlated with tumor status and colon polyps. ROC curve analysis showed that MAD2L2 expression has high diagnostic value in COAD. Analysis of immune infiltration results showed that MAD2L2 expression was positively correlated with neutrophil levels. The western blot results demonstrated that MAD2L2 was dose-dependently present with TNF-α. GO/KEGG revealed that MAD2L2 overexpressed and coexpressed genes were mostly involved in biological functions, including hypoxia response, response to reduced oxygen levels, mitochondrial translation elongation, and other processes. Conclusion: MAD2L2 as a new COAD biomarker contributes to our understanding of how alterations in gene expression and the immunological environment contribute to the development of colon cancer. Following further investigation, MAD2L2 may prove to be a viable target factor for clinical diagnosis and therapy of COAD.  相似文献   

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