Identification and structural analysis of human RBM8A and RBM8B: two highly conserved RNA-binding motif proteins that interact with OVCA1, a candidate tumor suppressor.

The OVCA1 gene is a candidate for the breast and ovarian tumor suppressor gene at chromosome 17p13.3. To help determine the function(s) of OVCA1, we used a yeast two-hybrid screening approach to identify OVCA1-associating proteins. One such protein, which we initially referred to as BOV-1 (binder of OVCA1-1) is 173 or 174 amino acids in length and appears to be a new member of a highly conserved RNA-binding motif (RBM) protein family that is highly conserved evolutionarily. Northern blot analysis revealed that BOV-1 is ubiquitously expressed and that three distinct messenger RNA species are expressed, 1-, 3.2-, and 5.8-kb transcripts. The 1-kb transcript is the most abundant and is expressed at high levels in the testis, heart, placenta, spleen, thymus, and lymphocytes. Using fluorescence in situ hybridization and the 5.8-kb complementary DNA probe, we determined that BOV-1 maps to both chromosome 5q13-q14 and chromosome 14q22-q23. Further sequence analysis determined that the gene coding the 1- and the 3.2-kb transcripts (HGMW-approved gene symbol RBM8A) maps to 14q22-q23, whereas a second highly related gene coding for the 5.8-kb transcript resides at chromosome 5q13-q14 (HGMW-approved gene symbol RBM8B). The predicted proteins encoded by RBM8A and RBM8B are identical except that RBM8B is 16 amino acids shorter at its N-terminus. Molecular modeling of the RNA-binding domain of RBM8A and RBM8B, based on homology to the sex-lethal protein of Drosophila, identifies conserved residues in the RBM8 protein family that are likely to contact RNA in a protein-RNA complex. The conservation of sequence and structure through such an evolutionarily divergent group of organisms suggests an important function for the RBM8 family of proteins.

[1]  K Autio,et al.  DNA copy number losses in human neoplasms. , 1999, The American journal of pathology.

[2]  P. King,et al.  Autoantibodies against the Hel‐N1 RNA‐binding protein among patients with lung carcinoma: An association with type I anti–neuronal nuclear antibodies , 1994, Annals of neurology.

[3]  M. Rosbash,et al.  Characterization of yeast U1 snRNP A protein: identification of the N-terminal RNA binding domain (RBD) binding site and evidence that the C-terminal RBD functions in splicing. , 1996, RNA.

[4]  Roland L. Dunbrack,et al.  Bayesian statistical analysis of protein side‐chain rotamer preferences , 1997, Protein science : a publication of the Protein Society.

[5]  J. Mattick,et al.  An RNA recognition motif in Wilms' tumour protein (WT1) revealed by structural modelling , 1996, Nature Genetics.

[6]  J. Millán,et al.  DECREASED EXPRESSION OF COLD-INDUCIBLE RNA-BINDING PROTEIN (CIRP) IN MALE GERM CELLS AT ELEVATED TEMPERATURE , 1999 .

[7]  C. Burd,et al.  Conserved structures and diversity of functions of RNA-binding proteins. , 1994, Science.

[8]  A. Sachs,et al.  Poly(A) tail metabolism and function in eucaryotes. , 1993, The Journal of biological chemistry.

[9]  A. Lamond RNA Processing: Wilms' tumour — the splicing connection? , 1995, Current Biology.

[10]  Roland L. Dunbrack,et al.  Comparative modeling of CASP3 targets using PSI‐BLAST and SCWRL , 1999, Proteins.

[11]  T. N. Bhat,et al.  The Protein Data Bank , 2000, Nucleic Acids Res..

[12]  E. Birney,et al.  Analysis of the RNA-recognition motif and RS and RGG domains: conservation in metazoan pre-mRNA splicing factors. , 1993, Nucleic acids research.

[13]  G. Thomas,et al.  Gene fusion with an ETS DNA-binding domain caused by chromosome translocation in human tumours , 1992, Nature.

[14]  S F Altschul,et al.  Iterated profile searches with PSI-BLAST--a tool for discovery in protein databases. , 1998, Trends in biochemical sciences.

[15]  D. Rio,et al.  Absence of interdomain contacts in the crystal structure of the RNA recognition motifs of Sex-lethal. , 1999, Proceedings of the National Academy of Sciences of the United States of America.

[16]  R. Darnell,et al.  The neuronal RNA binding protein Nova-1 recognizes specific RNA targets in vitro and in vivo , 1997, Molecular and cellular biology.

[17]  C. Burd,et al.  The determinants of RNA-binding specificity of the heterogeneous nuclear ribonucleoprotein C proteins. , 1994, The Journal of biological chemistry.

[18]  N. Nowak,et al.  MAGOH interacts with a novel RNA-binding protein. , 2000, Genomics.

[19]  Kazuki Kurimoto,et al.  Structural basis for recognition of the tra mRNA precursor by the Sex-lethal protein , 1999, Nature.

[20]  Roland L. Dunbrack,et al.  Prediction of protein side-chain rotamers from a backbone-dependent rotamer library: a new homology modeling tool. , 1997, Journal of molecular biology.

[21]  M. Ladomery,et al.  Multifunctional proteins suggest connections between transcriptional and post-transcriptional processes. , 1997, BioEssays : news and reviews in molecular, cellular and developmental biology.

[22]  A. Godwin,et al.  Expression of OVCA1, a candidate tumor suppressor, is reduced in tumors and inhibits growth of ovarian cancer cells. , 1999, Cancer research.

[23]  W. Wiszniewski,et al.  A novel hereditary developmental vitreoretinopathy with multiple ocular abnormalities localizing to a 5-cM region of chromosome 5q13-q14. , 1999, Ophthalmology.

[24]  Rahul C. Deo,et al.  Recognition of Polyadenylate RNA by the Poly(A)-Binding Protein , 1999, Cell.

[25]  T. Maniatis,et al.  Isolation of a complementary DNA that encodes the mammalian splicing factor SC35. , 1992, Science.

[26]  C. Burd,et al.  RNA binding specificity of hnRNP A1: significance of hnRNP A1 high‐affinity binding sites in pre‐mRNA splicing. , 1994, The EMBO journal.

[27]  Daniel St Johnston,et al.  The intracellular localization of messenger RNAs , 1995, Cell.

[28]  C. Gonnet,et al.  Wagner vitreoretinal degeneration with genetic linkage refinement on chromosome 5q13-q14 , 1999, Graefe's Archive for Clinical and Experimental Ophthalmology.

[29]  G. Dreyfuss,et al.  RNA-binding proteins as developmental regulators. , 1989, Genes & development.

[30]  C. Ghigna,et al.  Altered expression of heterogenous nuclear ribonucleoproteins and SR factors in human colon adenocarcinomas. , 1998, Cancer research.

[31]  C. Gilks,et al.  Chromosomal localization of a gene, GF1, encoding a novel zinc finger protein reveals a new syntenic region between man and rodents. , 1995, Cytogenetics and cell genetics.

[32]  F. Kittrell,et al.  Stage-specific changes in SR splicing factors and alternative splicing in mammary tumorigenesis , 1999, Oncogene.

[33]  R. Laskey,et al.  Two interdependent basic domains in nucleoplasmin nuclear targeting sequence: Identification of a class of bipartite nuclear targeting sequence , 1991, Cell.

[34]  Erich A. Nigg,et al.  Nucleocytoplasmic transport: signals, mechanisms and regulation , 1997, Nature.

[35]  D. Söll,et al.  Quality control mechanisms during translation. , 1999, Science.

[36]  A. Krainer,et al.  Crystal structure of human UP1, the domain of hnRNP A1 that contains two RNA-recognition motifs. , 1997, Structure.

[37]  M. Ladomery,et al.  Multiple roles for the Wilms' tumor suppressor, WT1. , 1999, Cancer research.

[38]  A. Godwin,et al.  Identification of two candidate tumor suppressor genes on chromosome 17p13.3. , 1996, Cancer research.

[39]  N. Hastie,et al.  The genetics of Wilms' tumor--a case of disrupted development. , 1994, Annual review of genetics.

[40]  Robert D. Goldman,et al.  Cells: a laboratory manual , 1997 .