The Drosophila developmental gene fat facets has a human homologue in Xp11.4 which escapes X-inactivation and has related sequences on Yq11.2.
EST 221 derived from human adult testis detects homology to the Drosophila fat facets gene (fat) and has related sequences on both the X and Y chromosomes mapping to Xp11.4 and Yq11.2 respectively. These two loci have been termed DFFRX and DFFRY for Drosophila fat facets related X and Y. The major transcript detected by EST 221 is-8 kb in size and is expressed widely in a range of 16 human adult tissues. RT-PCR analysis of 13 different human embryonic tissues with primers specific for the X and Y sequences demonstrates that both loci are expressed in developing tissues and quantitative RT-PCR of lymphoblastoid cell lines carrying different numbers of X chromosomes reveals that the X-linked gene escapes X-inactivation. The amino acid sequence (2547 residues) of the complete open reading frame of the X gene has 44% identity and 88% similarity to the Drosophila sequence and contains the conserved Cys and His domains characteristic of deubiquitinating enzymes, suggesting its biochemical function may be the hydrolysis of ubiquitin from protein-ubiquitin conjugates. The requirement of faf for normal oocyte development in Drosophila combined with the map location and escape from X-inactivation of DFFRX raises the possibility that the human homologue plays a role in the defects of oocyte proliferation and subsequent gonadal degeneration found in Turner syndrome.
Jones
M H
MH
University of Cambridge, Department of Pathology, UK.
Furlong
R A
RA
Burkin
H
H
Chalmers
I J
IJ
Brown
G M
GM
Khwaja
O
O
Affara
N A
NA
D000328:Adult; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002874:Chromosome Mapping; D017124:Conserved Sequence / Q000235:genetics; D018076:DNA, Complementary / Q000235:genetics; D004303:Dosage Compensation, Genetic; D004330:Drosophila / Q000235:genetics; D010450:Endopeptidases / Q000235:genetics*; D018507:Gene Expression Regulation, Developmental; D005796:Genes / Q000235:genetics*; D050437:Genes, Developmental; D006801:Humans; D008297:Male; D008969:Molecular Sequence Data; D009928:Organ Specificity; D012333:RNA, Messenger / Q000032:analysis; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D013737:Testis; D014960:X Chromosome / Q000235:genetics*; D014998:Y Chromosome / Q000235:genetics*
D018076:DNA, Complementary; D012333:RNA, Messenger; D010450:Endopeptidases; C059237:ubiquitin-Nalpha-protein hydrolase