摘要:

AbstractThe influence of the major histocompatibility complex (MHC) on the survival of H‐Y‐incompatible skin grafts in rats has been determined by challenging normal and previously sensitized females of various isogenic and congenic strains with male trunk or ear skin isografts. The MHC's influence on the potency of H‐Y has also been evaluated by determining the survival of male parental strain ear skin grafts on sensitized (with F1hybrid male cells) F1hybrid females of two different MHC congenic strains. The results indicate that, as in mice, the MHC has a dual affect on H‐Y; it is involved in determining the ability of females to respond to the antigen as well as influencing its

ISSN:0192-253X    

DOI:10.1002/dvg.1020080403

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractTo analyze the regulation of transthyretin gene expression we have produced transgenic mice by microinjecting cloned human transthyretin genes into fertilized eggs of C57BL/6 mice. The 7.6‐kilobase (kb) human transthyretin gene containing about 500 base pairs (bp) in the upstream region was used for microinjection. Seven out of nine transgenic mice had detectable amounts of human transthyretin in serum when analyzed by enzyme‐linked immunosorbent assay.Transthyretin mRNA was detected in liver and yolk sac but not in other tissues including brain. The amount of mRNA was variable among transgenic mice and was about one‐tenth of mouse endogenous transthyretin mRNA. Human and mouse transthyretin mRNAs were detected in liver of fetus and yolk sac at 13 days of gestation and unlike yolk sac the level of mRNA in liver increased gradually during development and reached the maximum at around 17 days of gestation. Human transthyretin was associated with mouse transthyretin to form tetramers as judged from the dilution curve of enzyme‐linked immu‐nosorbent assay and the spur formation in Ouchterl

ISSN:0192-253X    

DOI:10.1002/dvg.1020080404

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractThe majority of XX ↔ XY chimeric mice develop into fertile males. The sexual differentiation of the gonads in these animals has been examined on days 12–14 postcoitum to determine if their development parallels that of normal testes. It was found that 50% of chimeric fetuses, the proportion predicted to be XX ↔ XY, had neither normal testes nor ovaries. Instead, ovotestes were present, with varying proportions of presumptive ovarian and testicular tissue. On day 12 the ovotestes were organized with testicular tissue in the central region and ovarian tissue at the craniad and/or caudad poles. In the more advanced fetuses there was evidence of regression of the ovarian portion, which would account for the testes found in adults. These results are discussed in light of current theories of sex determination and differentiation and what was previously known about gonads of sex mo

ISSN:0192-253X    

DOI:10.1002/dvg.1020080405

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractFrom the data presented in this report, the humanLDHCgene locus is assigned to chromosome 11. Three genes determine lactate dehydrogenase (LDH) in man.LDHAandLDHBare expressed in most somatic tissues, while expression ofLDHCis confined to the germinal epithelium of the testes. A humanLDHCcDNA clone was used as a probe to analyze genomic DNA from rodent/human somatic cell hybrids. The pattern of bands withLDHChybridization is easily distinguished from the pattern detected byLDHAhybridization, and theLDHCprobe is specific for testis mRNA.The structural geneLDHAhas been previously assigned to human chromosome 11, whileLDHBmaps to chromosome 12. Studies of pigeon LDH have shown tight linkage betweenLDHBandLDHCleading to the expectation that these genes would be syntenic in man. However, the data presented in this paper show conclusively thatLDHCis syntenic withLDHAon human chromosome 11.The terminology for LDH genesLDHA, LDHB, andLDHCis equivalent toLdhl, Ldh2, andLdh3, respectively.

ISSN:0192-253X    

DOI:10.1002/dvg.1020080406

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractA human bacteriophage clone containing adult β‐globin genes with four Alu sequences was microinjected to produce transgenic mice. Southern blot analysis on the spleen of a transgenic mouse revealed an unusual hybridization pattern that suggested extensive dispersion of human DNA throughout the mouse genome. This pattern was reproducible using several restriction enzymes, including a noncutting enzyme. The hybridization pattern was not observed in other tissues, and sequences were not detected in progeny using the bacteriophage probe. However, hybridization of spleen DNA of offspring against a human Alu probe revealed genetic transmission of human Alu sequences. The results suggest dispersion of microinjected Alu sequences throughout the geno

ISSN:0192-253X    

DOI:10.1002/dvg.1020080407

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractAutosomal aneuploidy in mammals adversely affects developmental processes. In human beings, for example, trisomy 21 is the most frequent aneuploidy detected among newborns and the most common known genetic cause of mental retardation. In this review, several hypotheses are discussed that have been proposed to explain the mechanisms by which aneuploidy (especially trisomy) disrupts development. These mechanisms included specific gene dosage effects, generalized disruption of genetic homeostasis, and the influence of the parental origin of the duplicated chromosome. The availability of specific chromosomal rearrangements in mice, coupled with selective breeding schemes, permits generation of aneuploidy of specific chromosomes or chromosomal segments on controlled genetic backgrounds, thus enabling the systematic study of the causes and consequences of defined aneuploidy. Phenotypic characteristics associated with a number of specific aneuploidies in the mouse are discussed. Emphasis is placed on the effects of trisomy 16. Genetic homology between mouse chromosome 16 and human chromosome 21 has led investigators to suggest that analogous mechanisms will be responsible for the developmental abnormalities produced in these respective aneuploidies. Analysis of trisomy 16 mice from the organismal to the subcellular level has revealed a number of phenotypic characteristics (particularly neurobiologic ones) shared with human trisomy 21. The dosage effects of shared genes (or their products) may contribute to the development of these features.

ISSN:0192-253X    

DOI:10.1002/dvg.1020080408

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractIn this study, we examined the neurochemical profiles of selected brain regions (cerebral hemispheres, diencephalon/brainstem) in fetal (day 14 to 18 gestation) trisomy 19 (Ts19) mice. The neurochemical characteristics we observed in Ts19 mice were quite different from those we observed previously in Ts16 mice. Choline acetyltransferase (ChAT) activity was reduced significantly in the cerebral hemispheres, but not in the brainstem/diencephalon, of the fetal Ts19 mouse brain, suggesting a selective vulnerability of telencephalic cholinergic neurons. Additionally, the activity of glutamic acid decarboxylase (GAD) was reduced significantly in both hemispheres and diencephalon/brainstem of late gestation Ts19 fetuses, suggesting a selective vulnerability of GABAergic neurons as well. While the levels of catecholaminergic and dopaminergic markers were reduced significantly at late gestational ages, the relative rate of turnover of dopamine (DA), measured by the ratio of DOPAC/DA, was elevated significantly in Ts19 mice. Neither reduction in the thickness of various cellular zones of the cerebral cortex nor reduced cell density of the cerebral cortex accounts for the alterations in neurochemical parameters observed in Ts19 mice. These results suggest that the effects of the triplication of specific genes on the respective chromosomes, rather than a generalized disruption of developmental homeostasis resulting from extra chromosomal material, may produce selective alterations in neurochemical and neuroanatomical markers observed in these two mouse trisomies.

ISSN:0192-253X    

DOI:10.1002/dvg.1020080409

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractTechnological advances in the 1970s encouraged the mapping of homologous gene loci in different mammalian species, including mouse and man. One hundred eighty‐five homologous loci have now been mapped in these two species. Conservation of linkage is sufficient to identify substantial segments of the two genomes that have been left intact since their divergence from a common ancestor. The recognition of these conserved segments allows experimental manipulation of mouse chromosomes or chromosomal regions to produce models of human chromosomal anomalies of medical importance.Comparative gene mapping has been extended beyond mouse and man and the genomes of some species, including domestic cattle, appear to be more highly conserved relative to humans than the mouse. Such species may be particularly useful in providing models of human chromosomal anomalies that cannot be duplicated in laboratory mic

ISSN:0192-253X    

DOI:10.1002/dvg.1020080410

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractA cDNA clone of porcine alpha1acid glycoprotein (α1AGP) has been isolated and sequenced. Sequence homologies between porcine, human, and rat indicate that porcine α1AGP is similar in structure to the rat and human proteins. RNA blots from days 40, 60, 80, and 110 fetal, newborn, and adult livers showed that α1AGP mRNA is relatively abundant throughout fetal development, particularly at the later stages and in the newborn; there is a rapid decline in abundance following birth. From birth to 3 days of age, there is a three‐ to four‐fold decline in abundance, and α1AGP mRNA is approximately 100 times less abundant in the adult liver than in that of perinatal pigs. Southern blots showed that α1AGP is probably a single‐copy gene. The isolation of a cloned cDNA for porcine α1AGP provides a tool to investigate the molecular mechanisms involved in the developmental regulation of the gene and to correlate changes in gene expression during development with fetal growth and

ISSN:0192-253X    

DOI:10.1002/dvg.1020080411

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

ISSN:0192-253X    

DOI:10.1002/dvg.1020080402

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY