Showing papers by "Shuxun Yu published in 2011"

Label-Free Quantitative Proteomics Analysis of Cotton Leaf Response to Nitric Oxide

Abstract: To better understand nitric oxide (NO) responsive proteins, we investigated the proteomic differences between untreated (control), sodium nitroprusside (SNP) treated, and carboxy-PTIO potassium salt (cPTIO, NO scavenger) followed by SNP treated cotton plants. This is the first study to examine the effect of different concentrations of NO on the leaf proteome in cotton using a label-free approach based on nanoscale ultraperformance liquid chromatography-electrospray ionization (ESI)-low/high-collision energy MS analysis (MS(E)). One-hundred and sixty-six differentially expressed proteins were identified. Forty-seven of these proteins were upregulated, 82 were downregulated, and 37 were expressed specifically under different conditions. The 166 proteins were functionally divided into 17 groups and localized to chloroplast, Golgi apparatus, cytoplasm, and so forth. The pathway analysis demonstrated that NO is involved in various physiological activities and has a distinct influence on carbon fixation in photosynthetic organisms and photosynthesis. In addition, this is the first time proteins involved in ethylene synthesis were identified to be regulated by NO. The characterization of these protein networks provides a better understanding of the possible regulation mechanisms of cellular activities occurring in the NO-treated cotton leaves and offers new insights into NO responses in plants.

Inheritance of somatic embryogenesis using leaf petioles as explants in upland cotton

Abstract: Somatic embryogenesis (SE) is a critical step leading to plant regeneration in tissue culture of many plant species. The objective of the present study was to analyze the inheritance of SE in cotton (Gossypium hirsutum L.) using leaf petioles as explants. A high embryogenic callus (HEC)—producing line, W10, was selected by petiole callus culture from a commercial Chinese cotton cultivar CRI24 and crossed with a non embryogenic line, TM-1 and a low embryogenic (LEC) commercial Chinese cotton cultivar, CRI12, respectively. The parental lines, F1 and F2 were grown in field conditions for sources of leaf petioles as explants. The F1 plants were similar to the HEC parent in embryogenic callus (EC) induction, indicating that high EC ability is dominant. The classical Mendelian analysis showed that the high EC ability in the HEC line W10 is controlled by two independent dominant genes with complementary effect, designated Ec 1 and Ec 2 , while the LEC line CRI12 contains one dominant gene Ec 2 . A joint segregation analysis confirmed that SE ability in cotton is controlled by two major genes with epistatic effects along with other polygenes. A SSR marker analysis identified three quantitative trait loci (QTLs) on two linkage groups, one of which harbored a major QTL (qEc1) which is assigned to the major gene Ec 1 . This qualitative and quantitative genetic study has provided an incentive to fine map the genes responsible for SE towards the isolation of the SE genes in cotton.

Generation of ESTs for Flowering Gene Discovery and SSR Marker Development in Upland Cotton

Abstract: Background Upland cotton, Gossypium hirsutum L., is one of the world's most important economic crops. In the absence of the entire genomic sequence, a large number of expressed sequence tag (EST) resources of upland cotton have been generated and used in several studies. However, information about the flower development of this species is rare. Methodology/Principal Findings To clarify the molecular mechanism of flower development in upland cotton, 22,915 high-quality ESTs were generated and assembled into 14,373 unique sequences consisting of 4,563 contigs and 9,810 singletons from a normalized and full-length cDNA library constructed from pooled RNA isolated from shoot apexes, squares, and flowers. Comparative analysis indicated that 5,352 unique sequences had no high-degree matches to the cotton public database. Functional annotation showed that several upland cotton homologs with flowering-related genes were identified in our library. The majority of these genes were specifically expressed in flowering-related tissues. Three GhSEP (G. hirsutum L. SEPALLATA) genes determining floral organ development were cloned, and quantitative real-time PCR (qRT-PCR) revealed that these genes were expressed preferentially in squares or flowers. Furthermore, 670 new putative microsatellites with flanking sequences sufficient for primer design were identified from the 645 unigenes. Twenty-five EST–simple sequence repeats were randomly selected for validation and transferability testing in 17 Gossypium species. Of these, 23 were identified as true-to-type simple sequence repeat loci and were highly transferable among Gossypium species. Conclusions/Significance A high-quality, normalized, full-length cDNA library with a total of 14,373 unique ESTs was generated to provide sequence information for gene discovery and marker development related to upland cotton flower development. These EST resources form a valuable foundation for gene expression profiling analysis, functional analysis of newly discovered genes, genetic linkage, and quantitative trait loci analysis.

Cloning and expression of GhTM6 , a gene that encodes a B-class MADS-box protein in Gossypium hirsutum

Abstract: A full-length cDNA designated GhTM6, which encodes an organ differentiation-related B-class MADS-box protein, was isolated from Upland cotton (Gossipium hirsutum) by screening a normalized fulllength cDNA library and using a RT-PCR strategy. The translated sequence analysis indicated that the polypeptide contained MADS-box and K domains and had a classic TM6 motif, i.e., the paleoAP3 in the C-terminal region. The phylogenetic analysis showed that GhTM6 is closest to CeTM6, MaTM6, BuTM6, and PhTM6. Quantitative RT-PCR analysis showed that the GhTM6 gene was expressed at high levels in all tissues examined, such as those from squares, flowers, petals, stamens, and carpels under normal growth conditions. GhTM6 was expressed at high levels before floral initiation and declined thereafter. Furthermore, six stamens were seen in the transgenic tobacco flower as compared to five stamens in a wild-type flower. The results indicated that GhTM6 did not exhibit the full B-function spectrum, because it is only involved in the determination of stamen organ identity. However, its function in cotton will need to be examined in transgenic cotton plants.