A new homeodomain-leucine zipper gene from Arabidopsis thaliana induced by water stress and abscisic acid treatment

• Published in: Plant molecular biology 1998-05, Vol.37 (2), p.377-384
• Main Authors: Lee, Y.H. (Kumho Life and Environmental Science Lab., Kwangju-City (Korea Republic).), Chun, J.Y
• Format: Article
• Language: English
• Subjects: ABA; Abscisic acid; Abscisic Acid - pharmacology; Amino Acid Sequence; Amino acids; Arabidopsis - genetics; Arabidopsis Proteins; ARABIDOPSIS THALIANA; Base Sequence; CAJAS HOMEOTICAS; Cloning; Cloning, Molecular; Desiccation; DROUGHT STRESS; ESTRES DE SEQUIA; GENE; Gene Expression Regulation, Plant - drug effects; Gene Expression Regulation, Plant - physiology; GENES; Genes, Homeobox - genetics; Genes, Plant - genetics; HOMEOBOX; HOMEOBOXES; Homeodomain Proteins - genetics; LEUCINA; LEUCINE; Leucine Zippers; Molecular Sequence Data; Proteins; RNA, Messenger - analysis; RNA, Plant - analysis; Seedlings; Sequence Analysis, DNA; Sequence Homology, Amino Acid; Space life sciences; STRESS DU A LA SECHERESSE; Transcription Factors - genetics; Water; Water stress
• ISSN: 0167-4412; 1573-5028
• DOI: 10.1023/A:1006084305012

We report the isolation and characterization of a new homeobox gene from Arabidopsis thaliana using a polymerase chain reaction (PCR) cloning strategy. The full-length cDNA, designated Athb-12, encodes a protein of 235 amino acids. It contains the conserved DNA binding domain and the leucine zipper motif, characteristic of the homeodomain-leucine zipper family of transcription factors. The deduced amino acid sequence of Athb-12 shows over 80% identity to the Arabidopsis Athb-7 in the homeodomain (82%) and the leucine zipper motif (80%) of the proteins. However, outside the homeodomain and the leucine zipper motif, the homology is significantly lower. RNA analysis identified only one 0.96 kb transcript consistent with the size of Athb-12 cDNA. The Athb-12 transcript was detected in stem, leaf, flower and root as well as in seedlings. Treatment with water stress and exogenous abscisic acid (ABA) resulted in the accumulation of Athb-12 mRNA, similar to that of Athb-7. However, the time course of the Athb-12 response to ABA differed from that of Athb-7, suggesting that both genes, in response to ABA, are regulated in different manners. Taken together, these data suggest that Athb-12 and Athb-7 are members of a related gene family involved in the plant's response to water stress.