Expression of transcriptional repressor NC2alpha during Xenopus early embryogenesis.
To study the mechanisms behind the suppression of gene expression in the early phase of Xenopus development (cleavage stage), we conducted in silico cloning of the Xenopus transcriptional repressor NC2alpha. A search of the GenBank EST database using human NC2alpha as a probe identified Xenopus mitotic phosphoprotein 30 (xMP30) as a prime candidate for Xenopus NC2alpha (xNC2alpha). Full-length cDNA sequencing showed that xNC2alpha/xMP30 had a 68.9% identity at the amino acid level with its human counterpart. Northern blotting showed that xNC2alpha existed abundantly as a maternal mRNA. After the fertilization, the expression of xNC2alpha rapidly increased and reached a maximum 3 h before midblastula transition (MBT). Then its expression gradually decreased toward the early neurula stage. The expression profile of xNC2alpha mRNA is compatible with that of xNC2beta, which is the other component of the Xenopus NC2 transcriptional repressor.
Department of Biological Pharmaceutical Sciences, College of Pharmacy, Nihon University, 7-7-1 Narashino-dai, Funabashi, Chiba 274-8555, Japan. jfkugawa@pha.nihon-u.ac.jp
Fumihiko
F
Kugawa
Masashi
M
Yoneyama
Michiyo
M
Nagano
Yumi
Y
Koyama
Masatada
M
Aoki
Koichiro
K
Shiokawa
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000378:metabolism; D004625:Embryo, Nonmammalian / Q000378:metabolism*; D020224:Expressed Sequence Tags; D015723:Gene Library; D006801:Humans; D008969:Molecular Sequence Data; D010750:Phosphoproteins / Q000096:biosynthesis*; D012333:RNA, Messenger / Q000378:metabolism; D012335:RNA, Ribosomal / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D013997:Time Factors; D014157:Transcription Factors / Q000096:biosynthesis*; D014158:Transcription, Genetic; D014981:Xenopus; D029867:Xenopus Proteins / Q000096:biosynthesis*
D018076:DNA, Complementary; C467439:DRAP1 protein, Xenopus; D010750:Phosphoproteins; D012333:RNA, Messenger; D012335:RNA, Ribosomal; D014157:Transcription Factors; D029867:Xenopus Proteins; C075995:down-regulator of transcription 1