Disruption of Brachypodium lichenase alters metabolism of mixed-linkage glucan and starch
Research output: Contribution to journal › Journal article › Research › peer-review
Documents
- Preprint
Submitted manuscript, 21.2 MB, PDF document
- Accepted version
Accepted author manuscript, 21.3 MB, PDF document
Mixed-linkage glucan, which is widely distributed in grasses, is a polysaccharide highly abundant in cell walls of grass endosperm and young vegetative tissues. Lichenases are enzymes that hydrolyze mixed-linkage glucan first identified in mixed-linkage glucan-rich lichens. In this study, we identify a gene encoding a lichenase we name Brachypodium distachyon LICHENASE 1 (BdLCH1), which is highly expressed in the endosperm of germinating seeds and coleoptiles and at lower amounts in mature shoots. RNA in situ hybridization showed that BdLCH1 is primarily expressed in chlorenchyma cells of mature leaves and internodes. Disruption of BdLCH1 resulted in an eight-fold increase in mixed-linkage glucan content in senesced leaves. Consistent with the in situ hybridization data, immunolocalization results showed that mixed-linkage glucan was not removed in chlorenchyma cells of lch1 mutants as it was in wild type and implicate the BdLCH1 enzyme in removing mixed-linkage glucan in chlorenchyma cells in mature vegetative tissues. We also show that mixed-linkage glucan accumulation in lch1 mutants was resistant to dark-induced degradation, and 8-week-old lch1 plants showed a faster rate of starch breakdown than wild type in darkness. Our results suggest a role for BdLCH1 in modifying the cell wall to support highly metabolically active cells.
Original language | English |
---|---|
Journal | Plant Journal |
Volume | 109 |
Issue number | 4 |
Pages (from-to) | 927-939 |
ISSN | 0960-7412 |
DOIs | |
Publication status | Published - 2022 |
Bibliographical note
Publisher Copyright:
© 2021 Society for Experimental Biology and John Wiley & Sons Ltd
- BdLCH1, Brachypodium distachyon, chlorenchyma cells, lichenase, mixed-linkage glucan, starch
Research areas
ID: 288053365