Protective protein for beta-galactosidase, Ppgb, maps to the distal imprinting region of mouse chromosome 2 but is not imprinted.
Human chromosome 20 is conserved as a single segment on distal mouse chromosome (Chr) 2. PPGB, protective protein for beta-galactosidase, maps to human chromosome 20q13.1, and from linkage analysis of two interspecific crosses incorporating the mouse reciprocal translocations, T(2;8)2Wa (T2Wa) and T(2;16)28H (T28H), we have mapped the mouse homologue, Ppgb, to the conserved region on distal mouse Chr 2. From the combined data, the order of markers is T2Wa-Ada-Ppgb-D2Mit25-T28H. Loci mapping between the T2Wa and T28H breakpoints lie in a region that is subject to parental imprinting, and so expression of Ppgb was tested in mice with maternal duplication/paternal deficiency and its reciprocal for the distal region of Chr 2. We have shown by reverse transcription-polymerase chain reaction (RT-PCR) that both parental alleles of Ppgb were expressed in the brain and kidney of 17.5-day-old embryos, 18.5-day-old embryos, and newborn mice. Thus, Ppgb does not appear to be subject to imprinting effects in the mouse.
MRC Radiobiology Unit, Chilton, Didcot, Oxon, United Kingdom.
C M
CM
Williamson
E R
ER
Dutton
C V
CV
Beechey
J
J
Peters
D000818:Animals; D001483:Base Sequence; D002268:Carboxypeptidases / Q000235:genetics*; D043402:Cathepsin A; D002874:Chromosome Mapping; D002890:Chromosomes, Human, Pair 20; D017124:Conserved Sequence; D003433:Crosses, Genetic; D017931:DNA Primers / Q000235:genetics; D004827:Epilepsy / Q000235:genetics; D005260:Female; D008040:Genetic Linkage; D006023:Glycoproteins / Q000235:genetics*; D006801:Humans; D008297:Male; D051379:Mice; D008809:Mice, Inbred C3H; D008969:Molecular Sequence Data; D009115:Muridae; D013045:Species Specificity; D014178:Translocation, Genetic; D001616:beta-Galactosidase / Q000378:metabolism*
D017931:DNA Primers; D006023:Glycoproteins; D001616:beta-Galactosidase; D002268:Carboxypeptidases; C468629:CTSA protein, human; D043402:Cathepsin A