The murine orthologue of the Golgi-localized TPTE protein provides clues to the evolutionary history of the human TPTE gene family.
The human TPTE gene encodes a testis-specific protein that contains four potential transmembrane domains and a protein tyrosine phosphatase motif, and shows homology to the tumor suppressor PTEN/MMAC1. Chromosomal mapping revealed multiple copies of the TPTE gene present on the acrocentric chromosomes 13, 15, 21 and 22, and the Y chromosome. Zooblot analysis suggests that mice may possess only one copy of TPTE. In the present study, we report the isolation and initial characterization of the full-length cDNA of the mouse homologue Tpte. At least three different mRNA transcripts ( Tpte.a, b, c) are produced via alternative splicing, encoding predicted proteins that would contain four potential transmembrane domains and a protein tyrosine phosphatase motif. Transfection of a 5'EGFP-TPTE fusion protein in Hela cells revealed an intracellular localization within the Golgi apparatus. Tpte was mapped by radiation hybrid to a region of mouse chromosome 8 that shows conserved synteny with human 13q14.2-q21 between NEK3 and SGT1. This region of the human genome was found to contain a partial, highly diverged copy of TPTE that is likely to represent the ancestral copy from which the other copies of TPTE arose through duplication events. The Y chromosome copy of TPTE is a pseudogene and is not therefore involved in the testis expression of this gene family.
Guipponi
M
M
Division of Medical Genetics, University of Geneva Medical School, 1 rue Michel Servet, 1211 Geneva 4, Switzerland.
Tapparel
C
C
Jousson
O
O
Scamuffa
N
N
Mas
C
C
Rossier
C
C
Hutter
P
P
Meda
P
P
Lyle
R
R
Reymond
A
A
Antonarakis
S E
SE
D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D000818:Animals; D002451:Cell Compartmentation; D002874:Chromosome Mapping; D002882:Chromosomes, Human, Pair 13; D019143:Evolution, Molecular; D006056:Golgi Apparatus / Q000737:chemistry*; D006801:Humans; D008297:Male; D008565:Membrane Proteins / Q000235:genetics*; D051379:Mice; D008969:Molecular Sequence Data; D005810:Multigene Family / Q000235:genetics*; D051059:PTEN Phosphohydrolase; D010744:Phosphoric Monoester Hydrolases / Q000235:genetics; D010802:Phylogeny; D017027:Protein Tyrosine Phosphatases; D017386:Sequence Homology, Amino Acid; D025521:Tumor Suppressor Proteins / Q000235:genetics; D014714:Vertebrates / Q000145:classification / Q000235:genetics
D008565:Membrane Proteins; D025521:Tumor Suppressor Proteins; D010744:Phosphoric Monoester Hydrolases; D017027:Protein Tyrosine Phosphatases; C446603:TPTE protein, human; D051059:PTEN Phosphohydrolase; C494929:PTEN protein, human