Studies on a novel gene family

Studies on a novel gene family encoding putative


transcriptional regulators in deepwater rice and Arabidopsis

- 일시: 2001년 3월 30일(금요일) 오후 4시

- 연사: 김 정 회 박사


       MSU-DOE Plant Research Laboratory


       Michigan State University

- 장소: 생명관 104호 세미나실

-  문의처: 생명과학과 이영숙 교수(☎ 279-2296)

- Abstract


    Os-GRF1 (Oryza sativa-GROWTH-REGULATING FACTOR1)


was identified in a search for genes that are differentially


expressed in deepwater rice (Oryza sativa L.) internodes in


response to gibberellin (Van der Knaap et al., 2000). Os-GRF1


has two regions displaying general features of transcription


regulators, and contains a functional nuclear localization


signal. One of those two regions, named as QLQ domain, is


similar to a protein interaction domain of SWI2/SNF2, which


is a subunit of a chromatin-remodeling complex in yeast.


The other domain, WRC, is novel and found only in plant


proteins of unknown function. To study its role in plant


growth, Os-GRF1 was expressed in Arabidopsis. Bolting of


inflorescence stem of transformed plants was severely


inhibited, indicating that Os-GRF1 may play a regulatory


role in stem elongation.


In Arabidopsis thaliana, we have identified nine homologues


of Os-GRF1, named as GRL1 (GRF1-like) through GRL9. At-GRL


proteins show the same characteristic features, including


the highly conserved QLQ and WRC domains as does OsGRF1.


RNA gel blot and promoter::GUS fusion analyses show that


GRLs are highly expressed in the shoot tips, flowers, and


roots.


To determine the function of GRLs, we have identified T-DNA


insertional mutants for GRL1 through GRL3. However, we did


not observed a phenotype for those knock-out mutants under


different growing conditions and at different developmental


stages.


    


Apart from the reverse genetic approach, we are going


'forward' back again !

Van der Knaap E, Kim JH, Kende, H (2000) A novel


gibberellin-induced genes from rice and its potential


regulatory role in stem growth. Plant Physiol 122: 695-704