期刊
PLANT PHYSIOLOGY
卷 181, 期 2, 页码 595-608出版社
OXFORD UNIV PRESS INC
DOI: 10.1104/pp.19.00148
关键词
-
资金
- National Science Foundation (NSF) [IOS-53048]
- USDA \ National Institute of Food and Agriculture (NIFA) Hatch project [CONS00925]
- UConn Research Excellence Program
NAM, ATAF1/2 and CUC2 (NAC) domain transcription factors function as master switches in regulating secondary cell wall (SCW) biosynthesis in Arabidopsis (Arabidopsis thaliana) stems. Despite the importance of these NACs in fiber development, the upstream signal is still elusive. Using a large-scale mutant screening, we identified a dominant activation-tagging mutant, fiberless-d (fls-d), showing defective SCW development in stem fibers, similar to that of the nac secondary wall thickening promoting factor1-1 (nst1-1)nst3-3 double mutant. Overexpression of LATERAL ORGAN BOUNDARIES DOMAIN29 (LBD29) is responsible for the fls-d mutant phenotypes. By contrast, loss-of-function of LBD29, either in the dominant repression transgenic lines or in the transfer-DNA (T-DNA) insertion mutant lbd29-1, enhanced SCW development in fibers. Genetic analysis and transgenic studies demonstrated LBD29 depends on master regulators in mediating SCW biosynthesis, specifically NAC SECONDARY WALL THICKENING PROMOTING FACTOR1 (NST1), NST2, and NST3. Increasing indole-3-acetic acid (IAA) levels, either in stem tissues above a N-1-naphthylphthalamic acid-treated region or in plants directly sprayed with IAA, inhibits fiber wall thickening. The inhibition effect of naphthylphthalamic acid treatment and exogenous IAA application depends on a known auxin signaling pathway involving AUXIN RESPONSE FACTOR? (ARF7)/ARF19 and LBD29. These results demonstrate auxin is upstream of LBD29 in repressing NAC master regulators, and therefore shed new light on the regulation of SCW biosynthesis in Arabidopsis.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据