English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Background  Maize  brown midrib  ( bm ) mutants associated with impaired lignin biosynthesis are a potential source for the breed of novel germplasms with improved cell wall digestibility. The spontaneous  bm5  mutants had been identified since 2008. However, the gene responsible for the  bm5  locus, and the comprehensive effects of  bm5  mutation on lignin biosynthesis, soluble phenolics accumulation, and cell wall degradation have yet to be elucidated.    Results  The  bm5  locus was identified to encode a major 4-coumarate: coenzyme A ligase (Zm4CL1) through analyzing MutMap-assisted gene mapping data. Two alleles of  Zm4CL1  isolated from  bm5  mutants contained two transposons inserted in the first exon and the second intron, respectively, and consequently, the activities of 4CLs in the crude enzyme extracts from  bm5  midribs were reduced by 51–62% compared with the wild type. Furthermore, five  4CLs  were retrieved from maize genome, and  Zm4CL1  was the most highly expressed one in the lignified tissues. Mutation of  Zm4CL1  mainly impeded the biosynthesis of guaiacyl (G) lignins and increased the level of soluble feruloyl derivatives without impacting maize growth and development. Moreover, both neutral detergent fiber digestibility and saccharification efficiency of cell walls were significantly elevated in the  bm5  mutant.    Conclusions  Zm4CL1 was identified as the  Bm5  gene, since two independent alleles of  Zm4CL1  were associated with the same mutant phenotype. Mutation of  Zm4CL1  mainly affected G lignin biosynthesis and soluble feruloyl derivatives accumulation in maize lignified tissues. The reduced recalcitrance of the  bm5  mutant suggests that  Zm4CL1  is an elite target for cell wall engineering, and genetic manipulation of this gene will facilitate the utilization of crop straw and stover that have to be dealt with for environmental protection.    Electronic supplementary material  The online version of this article (10.1186/s13068-019-1421-z) contains supplementary material, which is available to authorized users.

Mutation of 4-coumarate: coenzyme A ligase 1 gene affects lignin biosynthesis and increases the cell wall digestibility in maize brown midrib5 mutants