HUA1, a regulator of stamen and carpel identities in Arabidopsis, codes for a nuclear RNA binding protein

Citation
Jj. Li et al., HUA1, a regulator of stamen and carpel identities in Arabidopsis, codes for a nuclear RNA binding protein, PL CELL, 13(10), 2001, pp. 2269-2281
Citations number
51
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Plant Sciences","Animal & Plant Sciences
Journal title
PLANT CELL
ISSN journal
1040-4651 → ACNP
Volume
13
Issue
10
Year of publication
2001
Pages
2269 - 2281
Database
ISI
SICI code
1040-4651(200110)13:10<2269:HAROSA>2.0.ZU;2-V
Abstract
Stamen and carpel identities are specified by the combinatorial activities of several floral homeotic genes, APETALA3, PISTILLATA, AGAMOUS (AG), SEPAL LATA1 (SEP1), SEPALLATA2 (SEP2), and SEPALLATA3 (SEP3), all of which code f or MADS domain DNA binding proteins. AG and the SEP genes also control flor al determinacy. HUA1 and HUA2 were identified previously as regulators of s tamen and carpel identities and floral determinacy because the recessive hu a1-1 or hua2-1 allele affected these processes in plants with a lower dosag e of functional AG (either homozygous for the weak ag-4 allele or heterozyg ous for the strong ag-1 allele). HUA2 was cloned previously and shown to co de for a novel protein. We isolated the HUA1 gene using a map-based approac h and show that it encodes a protein with six CCCH-type zinc finger motifs that is also found in yeast, Caenorhabditis elegans, Drosophila melanogaste r, and mammalian proteins. Several such genes from invertebrates and mammal s are known to play key regulatory roles in development. Therefore, HUA1 ar e another example of non-MADS domain proteins involved in organ identity sp ecification. We demonstrated that HUA1 binds ribohomopolymers, preferential ly poly rU and poly rG, but not double-stranded DNA in vitro. This finding suggests that HUA1, like several mammalian CCCH zinc finger proteins, is an RNA binding protein. Therefore, HUA1 likely participates in a new regulato ry mechanism governing flower development.