z-logo
Premium
Isolation of a maize bZIP protein subfamily: candidates for the ocs‐element transcription factor
Author(s) -
Foley Rhonda C.,
Grossman Carol,
Ellis Jeff G.,
Llewellyn Danny J.,
Dennis Elizabeth S.,
Peacock W. James,
Singh Karam B.
Publication year - 1993
Publication title -
the plant journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.058
H-Index - 269
eISSN - 1365-313X
pISSN - 0960-7412
DOI - 10.1111/j.1365-313x.1993.00669.x
Subject(s) - leucine zipper , subfamily , biology , genetics , complementary dna , transcription factor , promoter , cdna library , homology (biology) , consensus sequence , microbiology and biotechnology , peptide sequence , transcription (linguistics) , untranslated region , genomic dna , gene , messenger rna , gene expression , linguistics , philosophy
Summary Ocs‐elements, a family of 20 bp DNA sequences, are components of a number of promoters active in plants. In the maize BMS cell line the dominant ocs‐element binding activity is the ocs‐element transcription factor complex called OTF. The isolation of cDNA clones from a BMS cDNA expression library for two bZIP (basic region‐leucine zipper) proteins that bind the ocs‐element sequence and are good candidates for forming at least part of OTF is described. The two ocs‐element binding proteins, called OBF3.1 and OBF3.2, are closely related, with the OBF3.1 protein sharing 95.8% amino acid homology with part of the OBF3.2 protein although there were significant differences in the 3′ untranslated regions. Genomic Southern blot analysis revealed a small gene family with a minimum of two OBF3 loci mapping to chromosomes 3L 105 and 8L075. The OBF3.1 protein shared considerable homology with the wheat HBP1b protein (80% amino acid identity) and to a lesser extent with the tobacco TGA1a protein. OBF3.1 like HBP1b was able to bind well to the Hex sequence but poorly to G‐box/ABRE sequences. Interestingly, OBF3.1 bound eightfold more efficiently to an ocs‐element sequence than TGA1a, raising the possibility that OBF3.1 and TGA1a may be distinct members of an OBF3/TGA subfamily.

This content is not available in your region!

Continue researching here.

Having issues? You can contact us here