Identification and developmental expression of Xenopus hmga2beta.
HMGA proteins are "architectural modifiers" of the chromatin, characterized by three conserved "AT-hook" motifs, with which they bind AT-rich regions of the DNA, to assist in gene transcription. We report the identification and developmental expression of Xenopus laevis hmga2beta (Xlhmga2beta). We provide evidence of two forms of hmga2 (Xlhmga2alpha and Xlhmga2beta) and of a splicing variant for Xlhmga2beta with an additional AT-hook. By comparing X. laevis and X. tropicalis hmga2 DNA sequences to those of other organisms we show a high conservation of the Xlhmga2beta variant. By RT-PCR, Xlhmga2beta transcripts are first detected before the midblastula transition (MBT), and then become more abundant. By in situ hybridization, localized transcripts are first detected at neurula stages, in the presumptive central nervous system (CNS). At tailbud and tadpole stages, Xlhmga2beta mRNA is detected in the CNS, in the otic vesicles, in neural crest cell derivatives, in the notochord, and in the medio-lateral mesoderm.
Benini
Francesca
F
Dipartimento di Biologia, Laboratori di Biologia Cellulare e dello Sviluppo, Università di Pisa, via Carducci 13, 56010 Ghezzano (Pisa), Italy.
Onorati
Marco
M
Altamura
Sandro
S
Manfioletti
Guidalberto
G
Vignali
Robert
R
D017398:Alternative Splicing; D000595:Amino Acid Sequence; D000818:Animals; D004625:Embryo, Nonmammalian / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D025743:HMGA2 Protein / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D017386:Sequence Homology, Amino Acid; D029867:Xenopus Proteins / Q000235:genetics / Q000378:metabolism*; D014982:Xenopus laevis / Q000196:embryology / Q000378:metabolism*
D025743:HMGA2 Protein; C515772:HMGA2 protein, Xenopus; D029867:Xenopus Proteins