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排序方式: 共有410条查询结果,搜索用时 312 毫秒
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Assignment of cathepsin E (CTSE) to human chromosome region 1q31 by in situ hybridization and analysis of somatic cell hybrids 总被引:2,自引:0,他引:2
J M Couvreur T Azuma D A Miller M Rocchi T K Mohandas F A Boudi R T Taggart 《Cytogenetics and cell genetics》1990,53(2-3):137-139
A full length cathepsin E (CTSE) cDNA clone was used to assign the corresponding gene to human chromosome region 1q31 by in situ hybridization. Southern blot analysis of DNA from three independent human x rodent somatic cell hybrids containing X;1 translocations confirmed the assignment of the CTSE gene to the distal region of the long arm of chromosome 1. 相似文献
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R T Taggart I M Samloff L J Raffel A Graham C Cass G M Petersen J I Rotter M H Skolnick C E Schwartz G I Bell 《American journal of human genetics》1986,38(6):848-854
Pepsinogens (PGA) are the inactive precursors of pepsin, the major acid protease found in the stomach. The PGA gene family exhibits polymorphic variation in human populations that can either be demonstrated by electrophoretic analysis of the proteins or by analysis of the respective genes with cDNA probes. Here, we describe the interrelationships between the most common pepsinogen protein phenotypes and the corresponding pepsinogen haplotypes (A, B, and C) containing different combinations of the PGA3, PGA4, and PGA5 genes. We propose that this unusual genetic variation involving haplotypes that contain three, two, and one genes, respectively, is the result of molecular evolution by gene duplication. 相似文献
6.
Assignment of the pepsinogen gene complex (PGA) to human chromosome region 11q13 by in situ hybridization 总被引:5,自引:0,他引:5
The genes coding for human pepsinogen (PGA3, PGA4, and PGA5) were assigned to chromosome region 11q13 by in situ hybridization. Previously we localized the PGA gene complex to a centromeric region of chromosome 11 (p11----q13) by Southern blot analysis of mouse-human somatic cell hybrids. Our in situ hybridization results confirm this assignment and further localize the genes to a smaller region on the long arm. 相似文献
7.
Changes in the number and distribution of spermatozoa in the epididymis of the adult brown marsupial mouse were examined during July/August in mated and unmated males. The effects of mating on epididymal sperm populations were studied in 2 groups of males each mated 3 times and compared with the number and distribution of spermatozoa in the epididymides of 4 unmated control groups. One testis and epididymis were removed from each animal (hemicastration) either before or early in the mating season to provide information on initial sperm content and distribution. The contralateral side was removed later in the mating season to examine the effects of mating or sexual abstinence on epididymal sperm distribution. Epididymal sperm number peaked in both the distal caput and distal corpus/proximal cauda epididymidis in late July. The total number of spermatozoa, including those remaining in the testis, available to each male at the beginning of the mating season in early August was approximately 4.4 x 10(6)/side. Although recruitment of spermatozoa into the epididymis from the testis continued until mid-August, sperm content of the epididymis reached a peak of about 3.5 x 10(6)/epididymis in early August. At this time approximately 0.9 x 10(6) spermatozoa remained in the testis which had ceased spermatogenic activity. Throughout the mating season, epididymal spermatozoa were concentrated in the distal corpus/proximal cauda regions of the epididymis and were replenished by spermatozoa from upper regions of the duct. Relatively few spermatozoa were found in the distal cauda epididymidis, confirming a low sperm storage capacity in this region. A constant loss of spermatozoa from the epididymis, probably via spermatorrhoea, occurred throughout the mating season and very few spermatozoa remained in unmated males in late August before the annual male die-off. Mating studies showed that an average of 0.23 x 10(6) spermatozoa/epididymis were delivered per mating in this species, but the number of spermatozoa released at each ejaculation may be as few as 0.04 x 10(6)/epididymis when sperm loss via spermatorrhoea is taken into account. We suggest that the unusual structure of the cauda epididymidis, which has a very restricted sperm storage capacity, may function to limit the numbers of spermatozoa available at each ejaculation and thus conserve the dwindling epididymal sperm reserves in order to maximize the number of successful matings which are possible during the mating season. 相似文献
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J. T. Pang S. E. Lloyd C. Wooding B. Farren B. Pottinger B. Harding S. E. A. Leigh M. A. Pook R. V. Thakker F. J. Benham G. T. Gillett R. T. Taggart 《Human genetics》1996,97(6):732-741
Forty loci (16 polymorphic and 24 non-polymorphic) together with 23 cosmids isolated from a chromosome 11-specific library
were used to construct a detailed genetic map of 11p13-11g13. The map was constructed by using a panel of 13 somatic cell
hybrids that sub-divided this region into 19 intervals, a meiotic mapping panel of 33 multiple endocrine neoplasia type 1
(MEN1) families (134 affected and 269 unaffected members) and a mitotic mapping panel that was used to identify loss of heterozygosity
in 38 MENI-associated tumours. The results defined the most likely order of the 16 loci as being: 11pter-D11S871(D11S288,
D11S149)-11cen-CNTF-PGA-ROM1-D11S480-PYGM-SEA-D11S913-D115970-D11S97-D11S146-INT2-D11S971-D11S533-11gter. The meiotic mapping
studies indicated that the most likely location of the MEN1 gene was in the interval flanked by PYGM and D11S97, and the results
of mitotic mapping suggested a possible location of the MEN1 gene telomeric to SEA. Mapping studies of the gene encoding μ-calpain
(CAPN1) located CAPN1 to llg13 and in the vicinity of the MEN1 locus. However, mutational analysis studies did not detect
any germ-line CAPN1 DNA sequence abnormalities in 47 unrelated MEN1 patients and the results therefore exclude CAPN1 as the
MEN1 gene. The detailed genetic map that has been constructed of the 11p13-11g13 region should facilitate the construction
of a physical map and the identification of candidate genes for disease loci mapped to this region. 相似文献
10.
We have broadly defined the DNA regions regulating esterase6 activity in
several life stages and tissue types of D. melanogaster using P-
element-mediated transformation of constructs that contain the esterase6
coding region and deletions or substitutions in 5' or 3' flanking DNA.
Hemolymph is a conserved ancestral site of EST6 activity in Drosophila and
the primary sequences regulating its activity lie between -171 and -25 bp
relative to the translation initiation site: deletion of these sequences
decrease activity approximately 20-fold. Hemolymph activity is also
modulated by four other DNA regions, three of which lie 5' and one of which
lies 3' of the coding region. Of these, two have positive and two have
negative effects, each of approximately twofold. Esterase6 activity is
present also in two male reproductive tract tissues; the ejaculatory bulb,
which is another ancestral activity site, and the ejaculatory duct, which
is a recently acquired site within the melanogaster species subgroup.
Activities in these tissues are at least in part independently regulated:
activity in the ejaculatory bulb is conferred by sequences between -273 and
-172 bp (threefold decrease when deleted), while activity in the
ejaculatory duct is conferred by more distal sequences between -844 and
-614 bp (fourfold decrease when deleted). The reproductive tract activity
is further modulated by two additional DNA regions, one in 5' DNA (-613 to
-284 bp; threefold decrease when deleted) and the other in 3' DNA (+1860 to
+2731 bp; threefold decrease when deleted) that probably overlaps the
adjacent esteraseP gene. Collating these data with previous studies
suggests that expression of EST6 in the ancestral sites is mainly regulated
by conserved proximal sequences while more variable distal sequences
regulate expression in the acquired ejaculatory duct site.
相似文献