The Arabidopsis Domain of Unknown Function 1218 (DUF1218) Containing Proteins, MODIFYING WALL LIGNIN-1 and 2 (At1g31720/MWL-1 and At4g19370/MWL-2) Function Redundantly to Alter Secondary Cell Wall Lignin Content

被引：19

作者：

Mewalal, Ritesh ^{[1
,5
]}

Mizrachi, Eshchar ^{[1
]}

Coetzee, Berdine ^{[2
,3
]}

Mansfield, Shawn D. ^{[4
]}

Myburg, Alexander A. ^{[1
]}

机构：

[1] Univ Pretoria, FABI, Dept Genet, Private Bag X20, ZA-0028 Pretoria, South Africa

[2] Univ Pretoria, Dept Chem Engn, Private Bag X20, ZA-0028 Pretoria, South Africa

[3] Sappi Southern Africa, POB 12796, ZA-0087 Pretoria, South Africa

[4] Univ British Columbia, Fac Forestry, Dept Wood Sci, Forest Sci Ctr, 4030-2424 Main Mall, Vancouver, BC V6T 1Z4, Canada

[5] Oak Ridge Natl Lab, Biosci Div, BioEnergy Sci Ctr, Oak Ridge, TN 37831 USA

来源：

PLOS ONE | 2016年 / 11卷 / 03期

基金：

新加坡国家研究基金会;

关键词：

EXPRESSION; GENES; IDENTIFICATION; BIOLOGY; MALATE;

D O I：

10.1371/journal.pone.0150254

中图分类号：

O [数理科学和化学]; P [天文学、地球科学]; Q [生物科学]; N [自然科学总论];

学科分类号：

07 ; 0710 ; 09 ;

摘要：

DUF1218 is a land plant-specific innovation and has previously been shown to be associated with cell wall biology, vasculature patterning and abiotic/biotic stress response. The Arabidopsis genome encodes 15 members, two of which (At1g31720 and At4g27435) are preferentially expressed in the secondary cell wall depositing inflorescence stems. To further our understanding of the roles of DUF1218-containing proteins in secondary cell wall biology, we functionally characterized At1g31720 (herein referred to as MODIFYING WALL LIGNIN-1 or MWL-1). Since related gene family members may contribute to functional redundancy, we also characterized At4g19370 (MWL-2), the most closely related gene to MWL-1 in the protein family. Subcellular localization revealed that both Arabidopsis proteins are targeted to the cell periphery. The single T-DNA knockout lines, mwl-1 and mwl-2, and independent overexpression lines showed no significant differences in plant growth or changes in total lignin content relative to wild-type (WT) control plants. However, the double homozygous mutant, mwl-1/mwl-2, had smaller rosettes with a significant decrease in rosette fresh weight and stem height relative to the WT control at four weeks and six weeks, respectively. Moreover, mwl-1/mwl-2 showed a significant reduction in total lignin content (by ca. 11% relative to WT) and an increase in syringyl/guaiacyl (S/G) monomer ratio relative to the control plants. Our study has identified two additional members of the DUF1218 family in Arabidopsis as novel contributors to secondary cell wall biology, specifically lignin biosynthesis, and these proteins appear to function redundantly.

引用

页数：12