Duplications on human chromosome 22 reveal a novel Ret Finger Protein-like gene family with sense and endogenous antisense transcripts.
Analysis of 600 kb of sequence encompassing the beta-prime adaptin (BAM22) gene on human chromosome 22 revealed intrachromosomal duplications within 22q12-13 resulting in three active RFPL genes, two RFPL pseudogenes, and two pseudogenes of BAM22. The genomic sequence of BAM22vartheta1 shows a remarkable similarity to that of BAM22. The cDNA sequence comparison of RFPL1, RFPL2, and RFPL3 showed 95%-96% identity between the genes, which were most similar to the Ret Finger Protein gene from human chromosome 6. The sense RFPL transcripts encode proteins with the tripartite structure, composed of RING finger, coiled-coil, and B30-2 domains, which are characteristic of the RING-B30 family. Each of these domains are thought to mediate protein-protein interactions by promoting homo- or heterodimerization. The MID1 gene on Xp22 is also a member of the RING-B30 family and is mutated in Opitz syndrome (OS). The autosomal dominant form of OS shows linkage to 22q11-q12. We detected a polymorphic protein-truncating allele of RFPL1 in 8% of the population, which was not associated with the OS phenotype. We identified 6-kb and 1.2-kb noncoding antisense mRNAs of RFPL1S and RFPL3S antisense genes, respectively. The RFPL1S and RFPL3S genes cover substantial portions of their sense counterparts, which suggests that the function of RFPL1S and RFPL3S is a post-transcriptional regulation of the sense RFPL genes. We illustrate the role of intrachromosomal duplications in the generation of RFPL genes, which were created by a series of duplications and share an ancestor with the RING-B30 domain containing genes from the major histocompatibility complex region on human chromosome 6.
Seroussi
E
E
Department of Molecular Medicine, Karolinska Hospital, 171 76 Stockholm, Sweden.
Kedra
D
D
Pan
H Q
HQ
Peyrard
M
M
Schwartz
C
C
Scambler
P
P
Donnai
D
D
Roe
B A
BA
Dumanski
J P
JP
D033961:Adaptor Protein Complex 1; D033966:Adaptor Protein Complex beta Subunits; D000595:Amino Acid Sequence; D001483:Base Sequence; D002352:Carrier Proteins / Q000235:genetics*; D002892:Chromosomes, Human, Pair 22; D020451:Contig Mapping; D016373:DNA, Antisense / Q000235:genetics; D005260:Female; D020440:Gene Duplication; D006801:Humans; D008297:Male; D008565:Membrane Proteins / Q000235:genetics; D008957:Models, Genetic; D008969:Molecular Sequence Data; D005810:Multigene Family; D010375:Pedigree; D011110:Polymorphism, Genetic; D011544:Pseudogenes / Q000235:genetics; D017386:Sequence Homology, Amino Acid; D013577:Syndrome; D014018:Tissue Distribution; D014158:Transcription, Genetic
C439126:AP1B1 protein, human; D033961:Adaptor Protein Complex 1; D033966:Adaptor Protein Complex beta Subunits; D002352:Carrier Proteins; D016373:DNA, Antisense; D008565:Membrane Proteins; C400217:RFPL1 protein, human; C400218:RFPL2 protein, human; C400219:RFPL3 protein, human