Tissue-specific regulation by vitamin D3 of a novel protein containing ankyrin-like repeats.
Vitamin D3 is the precursor of the steroid hormone 1,25-dihydroxyvitamin D3 which is involved in the regulation of calcium metabolism, growth and differentiation. We used differential display of mRNA populations from kidney and intestine of vitamin D3-deficient and -replete chicks to determine the steady-state abundance of approximately 5000 mRNAs. One of these sequences, whose differential expression in kidney and down-regulation by vitamin D3 was confirmed by Northern analysis, was used to screen a cDNA library from vitamin D3-deficient chick kidney in order to obtain a full length cDNA. Subcloning and sequencing revealed that this cDNA encodes a novel protein containing ankyrin-like repeats and a C-terminal Fe-S binding region signature. The encoded protein consists of 617 amino acids and contains two sets of four ankyrin-like repeats separated by 146 amino acids. This motif consists of approximately 33 amino acids containing a highly conserved central hydrophobic alpha helix and is abundant in a wide variety of proteins, particularly those participating in the protein-protein or protein-membrane interactions involved in signal transduction, regulation of the cell cycle and control of transcription. Outside of the ankyrin-like domains, no homologies with other proteins in existing data bases were found. Our results have revealed a novel protein containing ankyrin-like repeats tissue-specifically down-regulated by vitamin D3 in the kidney.
Xu
J
J
Department of Biochemistry, University of California, Riverside 92521, USA.
Henry
H L
HL
D000595:Amino Acid Sequence; D000818:Animals; D017487:Ankyrins / Q000737:chemistry / Q000235:genetics*; D001483:Base Sequence; D015152:Blotting, Northern; D002478:Cells, Cultured; D002645:Chickens; D002762:Cholecalciferol / Q000494:pharmacology*; D018076:DNA, Complementary / Q000737:chemistry; D005786:Gene Expression Regulation / Q000187:drug effects*; D007668:Kidney / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D008969:Molecular Sequence Data; D012333:RNA, Messenger / Q000032:analysis; D012091:Repetitive Sequences, Nucleic Acid; D017422:Sequence Analysis, DNA; D014018:Tissue Distribution; D014808:Vitamin D Deficiency / Q000378:metabolism
D017487:Ankyrins; D018076:DNA, Complementary; D012333:RNA, Messenger; D002762:Cholecalciferol