Expression of CCAAT/enhancer binding protein delta is closely associated with degeneration of surface mucous cells of larval stomach during the metamorphosis of Xenopus laevis.
CCAAT/enhancer binding protein delta (C/EBP delta) is one of the transcription factors that have a basic-leucine zipper domain. In mammals, it has been suggested that this transcription factor plays a role in differentiation of adipocytes or in apoptosis of mammary gland epithelial cells. The factor also plays a role in acute-phase response in injury, infection and inflammation. We cloned Xenopus homologues of the C/EBP delta gene from metamorphosing stomach by subtractive hybridization and analyzed spatio-temporal expression pattern of the homologues. Two isoforms of C/EBP delta were isolated and named C/EBP delta-1 and -2. Their deduced amino acid sequences were highly similar to each other (identity, 91.2%). Expression of the C/EBP delta mRNAs in the stomach transiently increased during its metamorphosis-associated remodeling, and the transient up-regulation was also found in thyroid hormone-induced metamorphosis. The C/EBP delta mRNAs were exclusively localized in degenerating larval surface mucous cells, not in newly proliferating and differentiating adult-type epithelial cells. The result suggests a possibility that Xenopus C/EBP delta plays a role in apoptotic cell death of larval-type epithelium during the stomach remodeling.
Ikuzawa
Masayuki
M
Life Science Institute, Sophia University, Kioi-cho 7-1, Chiyoda-ku, Tokyo 102-8554, Japan.
Kobayashi
Ken-ichiro
K
Yasumasu
Shigeki
S
Iuchi
Ichiro
I
D000595:Amino Acid Sequence; D000818:Animals; D017209:Apoptosis; D051743:CCAAT-Enhancer-Binding Protein-delta; D022762:CCAAT-Enhancer-Binding Proteins / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D005753:Gastric Mucosa / Q000737:chemistry / Q000166:cytology / Q000254:growth & development*; D015870:Gene Expression / Q000187:drug effects; D006801:Humans; D007527:Isoenzymes / Q000145:classification / Q000235:genetics / Q000378:metabolism; D007814:Larva / Q000254:growth & development; D008675:Metamorphosis, Biological; D008969:Molecular Sequence Data; D010802:Phylogeny; D012333:RNA, Messenger / Q000032:analysis / Q000378:metabolism; D014157:Transcription Factors / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D014284:Triiodothyronine / Q000494:pharmacology; D014982:Xenopus laevis / Q000254:growth & development*
D022762:CCAAT-Enhancer-Binding Proteins; C497252:CEBPD protein, human; D007527:Isoenzymes; D012333:RNA, Messenger; D014157:Transcription Factors; D014284:Triiodothyronine; D051743:CCAAT-Enhancer-Binding Protein-delta