Role In Male Sterility Research Articles

Genome-Scale Analysis of the Grapevine KCS Genes Reveals Its Potential Role in Male Sterility.

Very long-chain fatty acid (VLCFA) synthesis in plants, is primarily rate-limited by the enzyme 3-ketoacyl CoA synthase (KCS), which also controls the rate and carbon chain length of VLCFA synthesis. Disruption of VLCFA during pollen development, may affect the pollen wall formation and ultimately lead to male sterility. Our study identified 24 grapevine KCS (VvKCS) genes and provided new names based on their relative chromosome distribution. Based on sequence alignment and phylogenetic investigation, these genes were grouped into seven subgroups, members of the same subgroup having similar motif structures. Synteny analysis of VvKCS genes, showed that the segmental duplication events played an important role in expanding this gene family. Expression profiles obtained from the transcriptome data showed different expression patterns of VvKCS genes in different tissues. Comparison of transcriptome and RT-qPCR data of the male sterile grape 'Y-14' and its fertile parent 'Shine Muscat', revealed that 10 VvKCS genes were significantly differentially expressed at the meiosis stage, which is a critical period of pollen wall formation. Further, joint analysis by weighted gene co-expression network analysis (WGCNA) and Kyoto Encyclopedia of Genes and Genomes (KEGG), revealed that five of these VvKCS (VvKCS6/15/19/20/24) genes were involved in the fatty acid elongation pathway, which may ultimately affect the structural integrity of the pollen wall in 'Y-14'. This systematic analysis provided a foundation for further functional characterization of VvKCS genes, with the aim of grapevine precision breeding improvement.

Genome-wide analysis of proline-rich extension-like receptor protein kinase (PERK) in Brassica rapa and its association with the pollen development

BackgroundProline-rich extension-like receptor protein kinases (PERKs) are an important class of receptor kinases located in the plasma membrane, most of which play a vital role in pollen development.ResultsOur study identified 25 putative PERK genes from the whole Brassica rapa genome (AA). Phylogenetic analysis of PERK protein sequences from 16 Brassicaceae species divided them into four subfamilies. The biophysical properties of the BrPERKs were investigated. Gene duplication and synteny analyses and the calculation of Ka/Ks values suggested that all 80 orthologous/paralogous gene pairs between B. rapa and A. thaliana, B. nigra and B. oleracea have experienced strong purifying selection. RNA-Seq data and qRT-PCR analyses showed that several BrPERK genes were expressed in different tissues, while some BrPERKs exhibited high expression levels only in buds. Furthermore, comparative transcriptome analyses from six male-sterile lines of B. rapa indicated that 7 BrPERK genes were downregulated in all six male-sterile lines. Meanwhile, the interaction networks of the BrPERK genes were constructed and 13 PERK coexpressed genes were identified, most of which were downregulated in the male sterile buds.ConclusionCombined with interaction networks, coexpression and qRT-PCR analyses, these results demonstrated that two BrPERK genes, Bra001723.1 and Bra037558.1 (the orthologs of AtPERK6 (AT3G18810)), were downregulated beginning in the meiosis II period of male sterile lines and involved in anther development. Overall, this comprehensive analysis of some BrPERK genes elucidated their roles in male sterility.

Hygienic safety characteristics of bottled water, used for potable water supply

On the basis of the results of performed analysis of literature references concerning influence of phthalates on population health indicators it was found out that their influence at prenatal period may lead to asthma development in children, as well as to allergy, obesity; they also provide anti-androgens effect, leading to growth inhibition and delay in sexual maturation, and to variance of systolic pressure. In case of men phthalates are associated with decreasing of testosterone level and sperms quality, that indicates at their possible role in male sterility. In case of women phthalates are associated with increase of the risk of the second type of diabetes appearance, as well as leiomyoma, endometriosis and breast carcinoma. Laboratory studies performed in accordance with Customs union’s technical regulation ТР ТС 005/2011 enabled to detect phthalates in the packages of bottled water, able to migrate into the bottled water. The results justify the necessity to monitor phthalates in bottled water.

Disrupted Genome Methylation in Response to High Temperature Has Distinct Affects on Microspore Abortion and Anther Indehiscence.

High-temperature (HT) stress induces male sterility, leading to yield reductions in crops. DNA methylation regulates a range of processes involved in plant development and stress responses, but its role in male sterility under HT remains unknown. Here, we investigated DNA methylation levels in cotton (Gossypium hirsutum) anthers under HT and normal temperature (NT) conditions by performing whole-genome bisulfite sequencing to investigate the regulatory roles of DNA methylation in male fertility under HT. Global disruption of DNA methylation, especially CHH methylation (where H = A, C, or T), was detected in an HT-sensitive line. Changes in the levels of 24-nucleotide small-interfering RNAs were significantly associated with DNA methylation levels. Experimental suppression of DNA methylation led to pollen sterility in the HT-sensitive line under NT conditions but did not affect the normal dehiscence of anther walls. Further transcriptome analysis showed that the expression of genes in sugar and reactive oxygen species (ROS) metabolic pathways were significantly modulated in anthers under HT, but auxin biosynthesis and signaling pathways were only slightly altered, indicating that HT disturbs sugar and ROS metabolism via disrupting DNA methylation, leading to microspore sterility. This study opens up a pathway for creating HT-tolerant cultivars using epigenetic techniques.

Cloning and Functional Analysis of MADS-box Genes, TaAG-A and TaAG-B, from a Wheat K-type Cytoplasmic Male Sterile Line

Wheat (Triticum aestivum L.) is a major crop worldwide. The utilization of heterosis is a promising approach to improve the yield and quality of wheat. Although there have been many studies on wheat cytoplasmic male sterility, its mechanism remains unclear. In this study, we identified two MADS-box genes from a wheat K-type cytoplasmic male sterile (CMS) line using homology-based cloning. These genes were localized on wheat chromosomes 3A and 3B and named TaAG-A and TaAG-B, respectively. Analysis of TaAG-A and TaAG-B expression patterns in leaves, spikes, roots, and stems of Chinese Spring wheat determined using quantitative RT-PCR revealed different expression levels in different tissues. TaAG-A had relatively high expression levels in leaves and spikes, but low levels in roots, while TaAG-B had relatively high expression levels in spikes and lower expression in roots, stems, and leaves. Both genes showed downregulation during the mononucleate to trinucleate stages of pollen development in the maintainer line. In contrast, upregulation of TaAG-B was observed in the CMS line. The transcript levels of the two genes were clearly higher in the CMS line compared to the maintainer line at the trinucleate stage. Overexpression of TaAG-A and TaAG-B in Arabidopsis resulted in phenotypes with earlier reproductive development, premature mortality, and abnormal buds, stamens, and stigmas. Overexpression of TaAG-A and TaAG-B gives rise to mutants with many deformities. Silencing TaAG-A and TaAG-B in a fertile wheat line using the virus-induced gene silencing (VIGS) method resulted in plants with green and yellow striped leaves, emaciated spikes, and decreased selfing seed set rates. These results demonstrate that TaAG-A and TaAG-B may play a role in male sterility in the wheat CMS line.

A CMS-Related Gene, Ψatp6-2, Causes Increased ATP Hydrolysis Activity of the Mitochondrial F1Fo-ATP Synthase and Induces Male Sterility in Pepper (Capsicum annuum L.)

Pollen formation is a complex process that is strictly controlled by genetic factors. Although many novel mitochondrial genes have been implicated in the dysfunction of mitochondrial enzymes and the cytoplasmic male sterility (CMS), there is little empirical evidence to show that CMS-related genes actually result in the dysfunction of enzyme and little is known about the regulatory mechanisms of the aberrant mitochondrial enzymes in male sterility in CMS lines. Here, we report the characterization of a novel mitochondrial gene, Ψatp6-2, which is hypothesized to play a role in male sterility in pepper. Using virus-induced gene silencing (VIGS), we observed that silencing the atp6-2 gene in the maintainer line resulted in an increase in ATP hydrolysis activity of the mitochondrial F1Fo-ATP synthase along with pollen abortion, while silencing the truncated Ψatp6-2 gene in the CMS line resulted in an inhibition of ATP hydrolysis activity and restoration of fertility. Altered ATP hydrolysis also affected the tolerance of the gene-silenced plants to abiotic stresses. Localization experiments showed that premature ATP hydrolysis occurred at the tetrad stage of pollen development in the CMS line, but no ATPase activity was observed in the microspores at the later stage. These results suggest that the Ψatp6-2 gene causes the alteration in ATP hydrolysis activity of the mitochondrial F1Fo-ATP synthase during pollen development, which eventually leads to male sterility in pepper.

The "drought-inducible" histone H1s of tobacco play no role in male sterility linked to alterations in H1 variants.

Tobacco ( Nicotiana tabacum L.) has two major H1 variants (H1A and H1B), which account for over 80% of chromatin linker histones, and four minor variants: H1C, H1D, H1E and H1F. We have shown previously [M. Prymakowska-Bosak et al. (1999) Plant Cell 11:2317-2329] that reversal of the natural proportion of major to minor H1 variants in transgenic tobacco plants results in a characteristic male-sterility phenotype identical to that occurring in many plant species subjected to water deficit at the time of male meiosis. It has been proposed by others that the drought-induced arrest of male gametophyte development is linked to decreased sugar delivery to reproductive tissues. Within the family of angiosperm H1s there is a well-defined class of minor H1 variants named "drought inducible" because some of its members have been shown to be induced by water deficit. We have identified and cloned the tobacco H1C gene, which, based on sequence similarity, represents a "drought-inducible" minor H1 variant. Analysis of the un-translated mRNA and promoter regions of H1C suggests a regulation by sucrose concentration. Antisense silencing of H1C and its close homologue H1D in plants that do not express H1A and H1B does not affect the characteristic H1A(-)/ H1B(-) male-sterility phenotype. Silencing of H1C and H1D also has no effect on growth and development of plants. Our findings demonstrate that H1C and H1D are dispensable for normal growth and development of tobacco, and that the compensatory up-regulation of "drought-inducible" H1s observed in H1A(-)/ H1B(-) plants is not the direct cause of male sterility linked to alterations in H1 variants.