44
views
0
recommends
+1 Recommend
0 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: found
      Is Open Access

      The maize brown midrib2 ( bm2) gene encodes a methylenetetrahydrofolate reductase that contributes to lignin accumulation

      research-article

      Read this article at

      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          The midribs of maize brown midrib ( bm) mutants exhibit a reddish-brown color associated with reductions in lignin concentration and alterations in lignin composition. Here, we report the mapping, cloning, and functional and biochemical analyses of the bm2 gene. The bm2 gene was mapped to a small region of chromosome 1 that contains a putative methylenetetrahydrofolate reductase (MTHFR) gene, which is down-regulated in bm2 mutant plants. Analyses of multiple Mu-induced bm2-Mu mutant alleles confirmed that this constitutively expressed gene is bm2. Yeast complementation experiments and a previously published biochemical characterization show that the bm2 gene encodes a functional MTHFR. Quantitative RT -PCR analyses demonstrated that the bm2 mutants accumulate substantially reduced levels of bm2 transcript. Alteration of MTHFR function is expected to influence accumulation of the methyl donor S-adenosyl- l -methionine (SAM). Because SAM is consumed by two methyltransferases in the lignin pathway (Ye et al., 1994), the finding that bm2 encodes a functional MTHFR is consistent with its lignin phenotype. Consistent with this functional assignment of bm2, the expression patterns of genes in a variety of SAM-dependent or -related pathways, including lignin biosynthesis, are altered in the bm2 mutant. Biochemical assays confirmed that bm2 mutants accumulate reduced levels of lignin with altered composition compared to wild-type. Hence, this study demonstrates a role for MTHFR in lignin biosynthesis.

          Related collections

          Most cited references43

          • Record: found
          • Abstract: not found
          • Article: not found

          Controlling the False Discovery Rate: A Practical and Powerful Approach to Multiple Testing

            Bookmark
            • Record: found
            • Abstract: found
            • Article: not found

            The genetics of lignin biosynthesis: connecting genotype to phenotype.

            The processes underlying lignification, which for many years have been the near-exclusive purview of chemists and biochemists, have more recently been approached using both classical forward genetic screens and targeted reverse genetic approaches such as antisense suppression, RNAi, and characterization of insertional mutants. In this review, we provide an overview of the current understanding of lignin biosynthesis and structure, with emphasis on mutant and transgenic plants that have contributed to this knowledge. We also discuss ongoing work aimed at elucidating the relationship between lignin structure and function in vivo, as well as the phenotypic consequences arising from genetic manipulation of the lignin biosynthetic pathway.
              Bookmark
              • Record: found
              • Abstract: found
              • Article: found
              Is Open Access

              Molecular mechanisms of eukaryotic pre-mRNA 3′ end processing regulation

              Messenger RNA (mRNA) 3′ end formation is a nuclear process through which all eukaryotic primary transcripts are endonucleolytically cleaved and most of them acquire a poly(A) tail. This process, which consists in the recognition of defined poly(A) signals of the pre-mRNAs by a large cleavage/polyadenylation machinery, plays a critical role in gene expression. Indeed, the poly(A) tail of a mature mRNA is essential for its functions, including stability, translocation to the cytoplasm and translation. In addition, this process serves as a bridge in the network connecting the different transcription, capping, splicing and export machineries. It also participates in the quantitative and qualitative regulation of gene expression in a variety of biological processes through the selection of single or alternative poly(A) signals in transcription units. A large number of protein factors associates with this machinery to regulate the efficiency and specificity of this process and to mediate its interaction with other nuclear events. Here, we review the eukaryotic 3′ end processing machineries as well as the comprehensive set of regulatory factors and discuss the different molecular mechanisms of 3′ end processing regulation by proposing several overlapping models of regulation.
                Bookmark

                Author and article information

                Journal
                Plant J
                Plant J
                tpj
                The Plant Journal
                BlackWell Publishing Ltd (Oxford, UK )
                0960-7412
                1365-313X
                February 2014
                10 January 2014
                : 77
                : 3
                : 380-392
                Affiliations
                [1 ]Department of Genetics, Development and Cell Biology, Iowa State University Ames, IA, 50011, USA
                [2 ]Department of Agronomy, Iowa State University 2035 Roy J. Carver Co-Lab, Ames, IA, 50011-3650, USA
                [3 ]Center for Plant Genomics, Iowa State University 2035 Roy J. Carver Co-Lab, Ames, IA, 50011-3650, USA
                [4 ]Department of Statistics, Iowa State University 2115 Snedecor, Ames, IA, 50011, USA
                Author notes
                *For correspondence (e-mails liu3zhen@ 123456ksu.edu (SL) or schnable@ 123456iastate.edu (PSS)).
                †Center for Cell Dynamics, Department of Biological Chemistry, Johns Hopkins University School of Medicine Baltimore, MD, 21205, USA
                ‡Department of Plant Pathology, Kansas State University Manhattan, KS, 66506, USA
                §Pioneer Hi-Bred International Inc. Johnston, IA, 50131, USA
                Article
                10.1111/tpj.12394
                4282534
                24286468
                eda5a916-a307-4b8f-8862-d70d0faa9b94
                © 2013 The Authors The Plant Journal © 2013 John Wiley & Sons Ltd.

                This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.

                History
                : 29 January 2013
                : 31 October 2013
                : 20 November 2013
                Categories
                Original Articles

                Plant science & Botany
                zea mays,brown midrib,lignin,methylenetetrahydrofolate,s-adenosyl-l-methionine

                Comments

                Comment on this article