Differential expression of two hemA mRNAs encoding glutamyl-tRNA reductase proteins in greening cucumber seedlings

被引：54

作者：

Tanaka, R ^{[1
]}

Yoshida, K ^{[1
]}

Nakayashiki, T ^{[1
]}

Masuda, T ^{[1
]}

Tsuji, H ^{[1
]}

Inokuchi, H ^{[1
]}

Tanaka, A ^{[1
]}

机构：

[1] KYOTO UNIV,FAC SCI,DEPT BIOPHYS,KYOTO 60601,JAPAN

来源：

PLANT PHYSIOLOGY | 1996年 / 110卷 / 04期

关键词：

D O I：

10.1104/pp.110.4.1223

中图分类号：

Q94 [植物学];

学科分类号：

071001 ;

摘要：

The first committed step of porphyrin synthesis in higher plants is the reduction of glutamyl-tRNA to glutamate 1-semialdehyde. This reaction is catalyzed by glutamyl-tRNA reductase, which is encoded by hemA genes. Two hemA cDNA clones (hemA1 and hemA2) were obtained from cucumber (Cucumis sativus) cotyledons by the PCR and cDNA library screening. They showed significant homology with published hemA sequences. Southern blot analysis of cucumber genomic DNA revealed that these genes are located at different loci and that there is another gene similar to the hemA genes. Accumulation of hemA1 mRNA was detected primarily in cotyledons and hypocotyls of greening cucumber seedlings, whereas that of hemA2 mRNA was detected in all tissues examined. Illumination of cucumber seedlings increased markedly the accumulation of hemA1 mRNA, but it did not induce remarkable changes in that of hemA2 mRNA. These findings suggest that hemA1 mRNA was accumulated in response to the demand of Chl synthesis in photosynthesizing tissues, whereas hemA2 mRNA was expressed in response to the demand of the synthesis of porphyrins other than chlorophylls.

引用

页码：1223 / 1230

页数：8

共 31 条

[1]

ANDREW TL, 1990, BIOSYNTHESIS HEME CH, P163

[2]

Ausubel FM, 1995, SHORT PROTOCOLS MOL

[3] CLONING AND EXPRESSION OF A STRUCTURAL GENE FROM CHLOROBIUM-VIBRIOFORME THAT COMPLEMENTS THE HEMA MUTATION IN ESCHERICHIA-COLI [J].