The Arabidopsis AS2 Gene Encoding a Predicted Leucine-zipper Protein Is Required for the Leaf Polarity Formation

作     者：徐轶 孙越 梁婉琪 黄海 

作者机构：中国科学院上海生命科学研究院上海植物生理生态研究所植物分子遗传国家重点实验室上海200032 

出 版 物：《Acta Botanica Sinica》 (Acta Botanica Sinica（植物学报：英文版）)

年 卷 期：2002年第44卷第10期

页      面：1194-1202页

核心收录：

学科分类：0710[理学-生物学] 07[理学] 09[农学] 071007[理学-遗传学] 0901[农学-作物学] 090102[农学-作物遗传育种] 

基　　金：国家"8 63"计划 (2 0 0 1AA225031) 上海市科委资助项目。~~ 

主　　题：Arabidopsis thaliana ASYMMETRIC LEAVES1 ASYMMETRIC LEAVES2 ERECTA leucine-zipper motif polarity formation 

摘      要：The asymmetric leaves2 ( as2) is a classical Arabidopsis thaliana (L.) Heynh. mutant that shows leaf lobes and leaflet-like structures from the petioles of leaves. Genetic and molecular analyses have demonstrated that the AS2 function is required for repression of meristem-related homeobox genes in leaves. In this study, we describe phenotypic characterizations of new as2 alleles that are in the Landsberg erecta (Ler) genetic background. In addition to the as2 phenotypes reported previously, the new as2 mutants have some leaves with petiole growth underneath the leaf blade, showing a lotus-leaf structure. More severe rosettes leaves of the as2 mutants form a filament-like structure, reflecting a loss of the adaxial-abaxial polarity in leaves. Among as2 mutants analyzed in different genetic backgrounds, only those that are in the Ler genetic background resulted in a high frequency of the lotus-leaf structure. We have isolated the AS2 gene by map-based gene cloning. The predicted AS2 protein contains a leucine-zipper motif, and its N-terminus shares high levels of sequence similarity to those of a group of predicted proteins with no known biological functions. AS2 transcripts were detected in leaves, flowers and fruits, but absent in stems, consistent with the mutant phenotypes.