Cloning and chromosome mapping of human retinoid X receptor beta: selective amino acid sequence conservation of a nuclear hormone receptor in mammals.
The murine retinoid X receptor beta (mRXR beta) is a nuclear hormone receptor that activates transcription of murine major histocompatibility complex (MHC) class I genes in response to retinoic acid. In this study, the human RXR beta gene was mapped onto the short arm or centromeric region of chromosome 6 (6pter-q13), which also harbors the MHC. Chromosomal localization was performed by Southern hybridization of genomic DNA from human rodent cell hybrids with the mRXR beta gene as a probe. In addition, a full-length cDNA clone encoding a human RXR beta was isolated by nucleic acid screening of a human cDNA library with a fragment of the mRXR beta gene as a probe. Comparison of the nucleotide-coding sequences of the human and the murine RXR beta revealed a predominance of third base substitutions, resulting in selective conservation of the predicted amino acid sequence of the proteins. The overall sequence homology was 97.6% on the amino acid level as opposed to 91.6% on the nucleotide level. In Northern hybridization experiments with the human cDNA as a probe, RXR beta gene transcripts were detected in a variety of human tumor cell lines, regardless of whether these cell lines expressed MHC class I genes.
Laboratory of Biochemical Immunogenetics, Memorial Sloan Kettering Cancer Center, New York, NY 10021.
K
K
Fleischhauer
O W
OW
McBride
J P
JP
DiSanto
K
K
Ozato
S Y
SY
Yang
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D002874:Chromosome Mapping; D002896:Chromosomes, Human, Pair 6; D003001:Cloning, Molecular; D017124:Conserved Sequence; D006224:Cricetinae; D015342:DNA Probes; D006801:Humans; D006822:Hybrid Cells; D008322:Mammals / Q000235:genetics; D051379:Mice; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000235:genetics*; D011956:Receptors, Cell Surface / Q000235:genetics*; D018168:Receptors, Retinoic Acid; D047488:Retinoid X Receptors; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D012689:Sequence Homology, Nucleic Acid; D014157:Transcription Factors
D015342:DNA Probes; D009687:Nuclear Proteins; D011956:Receptors, Cell Surface; D018168:Receptors, Retinoic Acid; D047488:Retinoid X Receptors; D014157:Transcription Factors