NOVEL MESSENGER-RNA SEQUENCES INDUCED BY INDOLE-3-ACETIC-ACID IN SECTIONS OF ELONGATING HYPOCOTYLS OF MUNG BEAN (VIGNA-RADIATA)

作者：YAMAMOTO KT; MORI H; IMASEKI H

来源：Plant and Cell Physiology, 1992, 33(1): 13-20.

• AUXIN
• CDNA CLONING
• GENE EXPRESSION
• HEAT-SHOCK GENE
• MEMBRANE PROTEIN
• VIGNA-RADIATA

Two cDNAs, ARG1 and ARG2, of auxin-regulated genes were isolated from sections of mung bean (Vigna radiata) hypocotyls by differential hybridization. ARG1 contained an open reading frame that encoded 380 amino acid residues (44.0 kDa). A computer analysis predicted that the deduced protein sequence included two membrane-spanning segments. ARG2 had the open reading frame that encoded 99 amino acid residues (10.5 kDa). No sequences with significant similarity to ARG1 or ARG2 were found in DNA and protein data banks. Northern blot analysis showed that an increase in levels of transcripts from the corresponding genes occurred after treatment of hypocotyl sections with 10(-7) M indole-3-acetic acid (IAA) for 1 h at 30-degrees-C, and a more than 10-fold increase in levels of arg1 mRNA occurred at 10(-5) M IAA, while levels of arg2 mRNA increased only four-fold. Plant hormones, such as abscisic acid, 6-benzylaminopurine and gibberellin, did not have any effect, but ethylene at 10-mu-l liter-1 had a slight stimulatory effect on levels of transcripts of both genes. Wounding also induced an increase in levels of transcripts of both genes: the effect was four-fold stronger than that of 10(-5) M IAA in the case of the arg1 gene, but was similar in the case of arg2. Heat-shock treatment was as effective as the treatment with IAA in the case of the arg2 gene. A barely detactable level of arg1 mRNA was present in elongating hypocotyls, while a considerable amount of the arg2 transcript was found. Arg2 is probably a heat-shock cognate gene.

• 出版日期1992-1