PubMed Central (PMC3 - NLM DTD)
Archive of life sciences journal literature at the U.S. National Institutes of Health (NIH), developed and managed by NIH's National Center for Biotechnology Information (NCBI) in the National Library of Medicine (NLM).
International Journal of Plant Genomics
Mostrando recursos 1 - 20 de 35
Methylation, Transcription, and Rearrangements of Transposable Elements in Synthetic Allopolyploids - Yaakov, Beery; Kashkush, Khalil
Transposable elements (TEs) constitute over 90% of the wheat genome. It was suggested that “genomic stress” such as hybridity or polyploidy might activate transposons. Intensive investigations of various polyploid systems revealed that allopolyploidization event is associated with widespread changes in genome structure, methylation, and expression involving low- and high-copy, coding and noncoding sequences. Massive demethylation and transcriptional activation of TEs were also observed in newly formed allopolyploids. Massive proliferation, however, was reported for very limited number of TE families in various polyploidy systems. The aim of this review is to summarize the accumulated data on genetic and epigenetic dynamics of...
Genes Encoding Callose Synthase and Phytochrome A Are Adjacent to a MAP3Kα-Like Gene in Beta vulgaris US H20 - Kuykendall, L. David; Shao, Jonathan Y.
MAP3Kα, a gene that encodes a key conserved protein kinase,
is responsible for initiating a rapid cascade of cellular events
leading to localized cell death. Hypersensitive response, as it is
termed, enables genetically resistant plants to limit microbial
invasion under the right environmental conditions. Since knowledge
of close physically linked genes is important for genome analysis
and possibly for improving disease resistance, systematic DNA
sequence analysis, gene annotation, and protein BLASTs were
performed to identify and characterize genes in close physical
proximity to a MAP3Kα-like gene in Beta vulgaris L. US H20. On the same 125 Kb BAC, callose synthase (BvCS)...
Marker-Assisted Breeding as Next-Generation Strategy for Genetic Improvement of Productivity and Quality: Can It Be Realized in Cotton? - Boopathi, N. Manikanda; Thiyagu, K.; Urbi, B.; Santhoshkumar, M.; Gopikrishnan, A.; Aravind, S.; Swapnashri, Gat; Ravikesavan, R.
The dawdling development in genetic improvement of cotton with conventional breeding program is chiefly due to lack of complete knowledge on and precise manipulation of fiber productivity and quality. Naturally available cotton continues to be a resource for the upcoming breeding program, and contemporary technologies to exploit the available natural variation are outlined in this paper for further improvement of fiber. Particularly emphasis is given to application, obstacles, and perspectives of marker-assisted breeding since it appears to be more promising in manipulating novel genes that are available in the cotton germplasm. Deployment of system quantitative genetics in marker-assisted breeding program...
Proteomic Analysis of Soybean Roots under Aluminum Stress - Duressa, Dechassa; Soliman, Khairy; Taylor, Robert; Senwo, Zachary
Toxic levels of aluminum (Al) in acid soils inhibit root growth and cause substantial reduction in yields of Al-sensitive crops. Aluminum-tolerant cultivars detoxify Al through multiple mechanisms that are currently not well understood at genetic and molecular levels. To enhance our understanding of the molecular mechanisms involved in soybean Al tolerance and toxicity, we conducted proteomic analysis of soybean roots under Al stress using a tandem combination of 2-D-DIGE, mass spectrometry, and bioinformatics tools and Al-tolerant (PI 416937) and Al-sensitive (Young) soybean genotypes at 6, 51 or 72 h of Al treatment. Comparison of the protein profile changes revealed that...
EM Algorithm for Mapping Quantitative Trait Loci in Multivalent Tetraploids - Li, Jiahan; Das, Kiranmoy; Fu, Guifang; Tong, Chunfa; Li, Yao; Tobias, Christian; Wu, Rongling
Multivalent tetraploids that include many plant species, such as potato, sugarcane, and rose,
are of paramount importance to agricultural production and biological research. Quantitative trait locus (QTL) mapping in multivalent tetraploids is challenged by their unique cytogenetic properties, such as double reduction. We develop a statistical method for mapping multivalent tetraploid QTLs by considering these cytogenetic properties. This method is built in the mixture model-based framework and implemented with the EM algorithm. The method allows the simultaneous estimation of QTL positions, QTL effects, the chromosomal pairing factor, and the degree of double reduction as well as the assessment of the estimation...
Identification of Aluminum Responsive Genes in Al-Tolerant Soybean Line PI 416937 - Duressa, Dechassa; Soliman, Khairy; Chen, Dongquan
Soybean is one of the most aluminum (Al) sensitive plants. The complex inheritance of Al tolerance trait has so far undermined breeding efforts to develop Al-tolerant soybeans. Discovering the genetic factors underlying the Al tolerance mechanisms would undoubtedly accelerate the pace of such endeavor. As a first step toward this goal, we analyzed the transcriptome profile in roots of Al-tolerant soybean line PI 416937 comparing Al-treated and untreated control plants using DNA microarrays. Many genes involved in transcription activation, stress response, cell metabolism and signaling were differentially expressed. Patterns of gene expression and mechanisms of Al toxicity and tolerance suggest...
Significance Test and Genome Selection in Bayesian Shrinkage Analysis - Che, Xiaohong; Xu, Shizhong
Bayesian shrinkage analysis is the state-of-the-art method for whole genome analysis of quantitative traits. It can estimate the genetic effects for the entire genome using a dense marker map. The technique is now called genome selection. A nice property of the shrinkage analysis is that it can estimate effects of QTL as small as explaining 2% of the phenotypic variance in a typical sample size of 300–500 individuals. In most cases, QTL can be detected with simple visual inspection of the entire genome for the effect because the false positive rate is low. As a Bayesian method, no significance test...
Transcriptomic Analysis of Starch Biosynthesis in the Developing Grain of Hexaploid Wheat - Stamova, Boryana S.; Laudencia-Chingcuanco, Debbie; Beckles, Diane M.
The expression of genes involved in starch synthesis in wheat was analyzed together with the accumulation profiles of soluble sugars, starch, protein, and starch granule distribution in developing caryopses obtained from the same biological materials used for profiling of gene expression using DNA microarrays. Multiple expression patterns were detected for the different starch biosynthetic gene isoforms, suggesting their relative importance through caryopsis development. Members of the ADP-glucose pyrophosphorylase, starch synthase, starch branching enzyme, and sucrose synthase gene families showed different expression profiles; expression of some members of these gene families coincided with a period of high accumulation of starch while...
Mapping Quantitative Trait Loci Using Distorted Markers - Xu, Shizhong; Hu, Zhiqiu
Quantitative trait locus (QTL) mapping is usually performed using markers that follow a Mendelian segregation ratio. We developed a new method of QTL mapping that can use markers with segregation distortion (non-Mendelian markers). An EM (expectation-maximization) algorithm is used to estimate QTL and SDL (segregation distortion loci) parameters. The joint analysis of QTL and SDL is particularly useful for selective genotyping. Application of the joint analysis is demonstrated using a real life data from a wheat QTL mapping experiment.
Reproducible RNA Preparation from Sugarcane and Citrus for Functional Genomic Applications - Damaj, Mona B.; Beremand, Phillip D.; Buenrostro-Nava, Marco T.; Riedel, Beth; Molina, Joe J.; Kumpatla, Siva P.; Thomas, Terry L.; Mirkov, T. Erik
High-throughput functional genomic procedures depend on the quality of the RNA used. Copurifying molecules can negatively impact the functionality of some plant RNA preparations employed in these procedures. We present a simplified, rapid, and scalable SDS/phenol-based method that provides the high-quantity and -quality RNA required by the newly emerging biotechnology applications. The method is applied to isolating RNA from tissues of two biotechnologically important crop plants, sugarcane and citrus, which provide a challenge due to the presence of fiber, polysaccharides, or secondary metabolites. The RNA isolated by this method is suitable for several downstream applications including northern blot hybridization, microarray...
PROC QTL—A SAS Procedure for Mapping Quantitative Trait Loci - Hu, Zhiqiu; Xu, Shizhong
Statistical analysis system (SAS) is the most comprehensive statistical analysis software package in the world. It offers data analysis for almost all experiments under various statistical models. Each analysis is performed using a particular subroutine, called a procedure (PROC). For example, PROC ANOVA performs analysis of variances. PROC QTL is a user-defined SAS procedure for mapping quantitative trait loci (QTL). It allows users to perform QTL mapping for continuous and discrete traits within the SAS platform. Users of PROC QTL are able to take advantage of all existing features offered by the general SAS software, for example, data management and...
Molecular Cytogenetic Mapping of Chromosomal Fragments and Immunostaining of Kinetochore Proteins in Beta - Dechyeva, Daryna; Schmidt, Thomas
By comparative multicolor FISH, we have physically mapped small chromosome fragments in the sugar beet addition lines PRO1 and PAT2 and analyzed the distribution of repetitive DNA families in species of the section Procumbentes of the genus Beta. Six repetitive probes were applied, including genotype-specific probes—satellites pTS4.1, pTS5, and pRp34 and a dispersed repeat pAp4, the telomere (TTTAGGG)n, and the conserved 18S-5.8S-25S rRNA genes. Pachytene-FISH analysis of the native centromere organization allowed proposing the origin of PRO1 and PAT2 fragments. Comparative analysis of the repetitive DNA distribution and organization in the wild beet and in the addition lines allowed the...
Structural Characterization and Expression Analysis of the SERK/SERL Gene Family in Rice (Oryza sativa) - Singla, Bhumica; Khurana, Jitendra P.; Khurana, Paramjit
Somatic embryogenesis (SE) is the developmental restructuring of somatic cells towards the embryogenic pathway and forms the basis of cellular totipotency in angiosperms. With the availability of full-length cDNA sequences from Knowledge-based Oryza Molecular Biological Encylopedia (KOME), we identified the leucine-rich repeat receptor-like kinase (LRR-RLK) genes from rice (Oryza sativa), which also encompasses genes involved in regulating somatic embryogenesis. Eight out of eleven of the rice SERK and SERL (SERK-like) genes have the TIGR annotation as (putative) brassinosteroid insensitive 1-associated receptor kinase (precursor). Real-time polymerase chain reaction analysis was undertaken to quantify transcript levels of these 11 genes. Most of...
Statistical Analysis of Efficient Unbalanced Factorial
Designs for Two-Color Microarray Experiments - Tempelman, Robert J.
Experimental designs that efficiently embed a fixed effects treatment structure within a random effects design structure typically require a mixed-model approach to data analyses. Although mixed model software tailored for the analysis of two-color microarray data is increasingly available, much of this software is generally not capable of correctly analyzing the elaborate incomplete block designs that are being increasingly proposed and used for factorial treatment structures. That is, optimized designs are generally unbalanced as it pertains to various treatment comparisons, with different specifications of experimental variability often required for different treatment factors. This paper uses a publicly available microarray dataset,...
Development in Rice Genome Research Based on
Accurate Genome Sequence - Matsumoto, Takashi; Wu, Jianzhong; Antonio, Baltazar A.; Sasaki, Takuji
Rice is one of the most important crops in the world. Although genetic improvement is a key technology for the acceleration of rice breeding, a lack of genome information had restricted efforts in molecular-based breeding until the completion of the high-quality rice genome sequence, which opened new opportunities for research in various areas of genomics. The syntenic relationship of the rice genome to other cereal genomes makes the rice genome invaluable for understanding how cereal genomes function. Producing an accurate genome sequence is not an easy task, and it is becoming more important as sequence deviations among, and even within,...
Coe1 in Beta vulgaris L. Has a Tnp2-Domain DNA Transposase Gene within Putative LTRs and Other Retroelement-Like Features - Kuykendall, David; Shao, Jonathan; Trimmer, Kenneth
We describe discovery in Beta vulgaris L. of Coe1, a DNA transposase gene within putative long terminal repeats (LTRs), and other retrotransposon-like features including both a retroviral-like hypothetical gene and an Rvt2-domain reverse transcriptase pseudogene. The central DNA transposase gene encodes, in eight exons, a predicted 160-KDa protein producing BLAST alignments with En/Spm-type transposons. Except for a stop signal, another ORF encodes a Ty1-copia-like reverse transcriptase with amino acid sequence domain YVDDIIL. Outside apparent LTRs, an 8-mer nucleotide sequence motif CACTATAA, near or within inverted repeat sequences, is hypothetical extreme termini. A genome scan of Arabidopsis thaliana found another example...
Application of Association Mapping to Understanding the Genetic Diversity of Plant Germplasm Resources - Abdurakhmonov, Ibrokhim Y.; Abdukarimov, Abdusattor
Compared to the conventional linkage mapping, linkage disequilibrium (LD)-mapping, using the nonrandom associations of loci in haplotypes, is a powerful high-resolution mapping tool for complex quantitative traits. The recent advances in the development of unbiased association mapping approaches for plant population with their successful applications in dissecting a number of simple to complex traits in many crop species demonstrate a flourish of the approach as a powerful gene tagging tool for crops in the plant genomics era of 21st century. The goal of this review is to provide nonexpert readers of crop breeding community with (1) the basic concept, merits,...
Statistical Methods for Mapping Multiple QTL - Zou, Wei; Zeng, Zhao-Bang
Since Lander and Botstein proposed the interval mapping method for QTL mapping data analysis in 1989, tremendous progress has been made in the last many years to advance new and powerful statistical methods for QTL analysis. Recent research progress has been focused on statistical methods and issues for mapping multiple QTL together. In this article, we review this progress. We focus the discussion on the statistical methods for mapping multiple QTL by maximum likelihood and Bayesian methods and also on determining appropriate thresholds for the analysis.
Rice Molecular Breeding Laboratories in the Genomics Era: Current Status and Future Considerations - Collard, Bert C. Y.; Vera Cruz, Casiana M.; McNally, Kenneth L.; Virk, Parminder S.; Mackill, David J.
Using DNA markers in plant breeding with marker-assisted selection (MAS) could greatly improve the precision and efficiency of selection, leading to the accelerated development of new crop varieties. The numerous examples of MAS in rice have prompted many breeding institutes to establish molecular breeding labs. The last decade has produced an enormous amount of genomics research in rice, including the identification of thousands of QTLs for agronomically important traits, the generation of large amounts of gene expression data, and cloning and characterization of new genes, including the detection of single nucleotide polymorphisms. The pinnacle of genomics research has been the...