TAP Family: VOZ

Mitsuda et al (2004): A 38-bp pollen-specific cis-acting region of the AVP1 gene is involved in the expression of the Arabidopsis thaliana V-PPase during pollen development. Here, we report the isolation and structural characterization of AtVOZ1 and AtVOZ2, novel transcription factors that bind to the 38-bp cis-acting region of A. thaliana V-PPase gene, AVP1. AtVOZ1 and AtVOZ2 show 53% amino acid sequence similarity. Homologs of AtVOZ1 and AtVOZ2 are found in various vascular plants as well as a moss, Physcomitrella patens. Promoter-beta-glucuronidase reporter analysis shows that AtVOZ1 is specifically expressed in the phloem tissue and AtVOZ2 is strongly expressed in the root. In vivo transient effector-reporter analysis in A. thaliana suspension-cultured cells demonstrates that AtVOZ1 and AtVOZ2 function as transcriptional activators in the Arabidopsis cell. Two conserved regions termed Domain-A and Domain-B were identified from an alignment of AtVOZ proteins and their homologs of O. sativa and P. patens. AtVOZ2 binds as a dimer to the specific palindromic sequence, GCGTNx7ACGC, with Domain-B, which is comprised of a functional novel zinc coordinating motif and a conserved basic region. Domain-B is shown to function as both the DNA-binding and the dimerization domains of AtVOZ2. From highly the conservative nature among all identified VOZ proteins, we conclude that Domain-B is responsible for the DNA binding and dimerization of all VOZ-family proteins and designate it as the VOZ-domain.

This TAP family belongs to the GCM domain factors structural class of the Beta-hairpin exposed by an alpha/beta-scaffold structural superclass, as defined in Plant-TFClass (Blanc-Mathieu et al. 2024)

References:

Mitsuda, N; Hisabori, T; Takeyasu, K; Sato, MH. 2004. VOZ; isolation and characterization of novel vascular plant transcription factors with a one-zinc finger from Arabidopsis thaliana. Plant Cell Physiol. 45(7):845-54

Blanc-Mathieu, Romain et al. 2024. Plant-TFClass: a structural classification for plant transcription factors. Trends in Plant Science, Volume 29, Issue 1, 40 - 51