VOZ; Isolation and Characterization of Novel Vascular Plant Transcription Factors with a One-Zinc Finger from Arabidopsis thaliana

Abstract

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.

Vascular plant one-zinc-finger protein 2 is localized both to the nucleus and stress granules under heat stress in Arabidopsis

“…Although VOZ proteins were speculated to function as transcriptional activators, 15 no clear localization of VOZ has ever been observed in the nucleus under normal growth conditions. In this study, we showed that VOZ2 is transferred from the cytosol to the nucleus under heat stress conditions (Fig.…”

“…We previously reported that VOZ proteins in higher plants have a well-conserved unconventional CCCH zinc-finger motif, which functions as the DNA-binding domain of VOZ-family proteins. 15 Taking VOZ proteins as P-body-and SG-associated CCCH-type zinc proteins into consideration, VOZs may have an ability to bind to RNA and to participate in sequestration of particular mRNAs under heat stress for turnover and translational repression of specific mRNAs.…”

“…VOZ proteins share a considerable homology with the NAC protein family in the Cterminal basic region and are classified into NAC subgroup VIII-2. 15 Recently, VOZs were found to interact with phytochrome B and to upregulate flowering locus T (FT) and downregulate flowering locus C (FLC). 16 We previously reported that the voz1voz2 double mutant shows increased cold and drought tolerance but decreased resistance to pathogens and heat stress.…”

The Phytochrome-Interacting VASCULAR PLANT ONE–ZINC FINGER1 and VOZ2 Redundantly Regulate Flowering in Arabidopsis

“…Among candidates for phyB-interacting factors were VOZ1 and VOZ2, which have a zinc-finger motif and transcriptional activator activities (Mitsuda et al, 2004). VOZ1 and VOZ2 belong to the subgroup VIII-2 of the NAC proteins, which comprise one of the largest transcription factor families in plants (Jensen et al, 2010).…”

Screening of Tissue-Specific Genes and Promoters in Tomato by Comparing Genome Wide Expression Profiles of Arabidopsis Orthologues

“…Seed-and fruit-specific E273715 contain four seed-related ciselements (ABREOSRAB21, Marcotte et al, 1989; CANBNNA-PA, Ellerström et al, 1996;EMBP1TAEM, Guiltinan et al, 1990;GADOWNAT, Ogawa et al, 2003) but do not contain fruit-related cis-elements. In the cases of E254367 (flower-and fruit-specific) and E541096 (flower specific) promoters, there were several flower-and pollen-related regulatory elements (VOZATVPP, Mitsuda et al, 2004;POLLEN1LELAT52, Bate and Twell, 1998;AGAMOUSATCONSENSUS, Shiraishi et al, 1993). In particular, we found that E254367 contains fruitspecific cis-elements (TGTCACACUCUMSIN, Yamagata et al, 2002;Fig.…”