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81.
82.
A biochemical genetic study of the enzyme malate dehydrogenase (MDH) was conducted in the grasshopperOxya j. japonica. Analysis of MDH electrophoretic variation in this species of grasshopper shows that one of the two autosomal loci for MDH in grasshoppers, the Mdh-2 locus, controlling the anodal set of MDH isozymes, is duplicated. Results of breeding studies confirm this and the observed polymorphism at theMdh-2 locus in the two populations ofOxya j. japonica studied can be attributed to three forms of linked alleles at the duplicated locus in equilibrium in both populations. In this respect, all individuals of this species possess heterozygous allelic combinations at the duplicatedMdh-2 locus, which may account for the spread of the duplicated locus in the populations of this species of grasshopper.This research was supported by a grant (Vote F) from the University of Malaya, Kuala Lumpur. 相似文献
83.
Long-term expression of gene introduction into normal human T-lymphocytes by retroviral-mediated gene transfer 总被引:1,自引:0,他引:1
A A Fauser 《Journal of cellular biochemistry》1991,45(4):353-358
Human T-lymphocytes are long lived, easily accessible, mature, and capable of proliferation. They are theoretically a suitable target for retroviral mediated gene transfer. To test this hypothesis, normal human T-cells obtained from bone marrow and peripheral blood were stimulated with phytohemagglutinin (PHA) and infected 24 h later with the retroviral vector N2 which carries the bacterial neo gene. T-lymphocytes were propagated in culture for up to 14 weeks with interleukin-2 (IL-2). Analysis by whole cell RNA dot/blot using a single stranded RNA probe demonstrated persistent expression of the neo gene. Preliminary functional studies revealed that both helper and suppressor functions were preserved in the infected cells in culture. These results demonstrate that normal T-cells are capable of long-term expression of genes introduced by retroviral mediated gene transfer and are potential target cells for somatic gene therapy. 相似文献
84.
A simple method for shortening a plasmid genome using a system of plasmid cointegration mediated by a Tn3 mutant 总被引:3,自引:0,他引:3
This paper describes a simple method for the isolation of small plasmids of various sizes from pSMI, a derivative of the resistance plasmid R 100. The method is based on the observation that a repressor-negative mutant of the ampicillin-resistance (ampr) transposon Tn3, Tn3 No. 5, mediates cointegration of a plasmid carrying Tn 3 No. 5 (pMB8::Tn 3 No. 5) into virtually any site on pSMI. The resulting cointegrate plasmids contain the pSMI sequence which is joined with the ampr gene of the Tn 3 mutant. This cointegration is so frequent that large cointegrate plasmids can be readily detected in the total plasmid DNA prepared from cells carrying pSMI and pMB8::Tn3 No. 5. We were able to isolate small plasmids of various sizes by digesting the total plasmid DNAs with restriction endonucleases which cut both pSM 1 and Tn3 No. 5 sequences present in the cointegrates and subsequently ligating the restriction fragment containing both the ampr gene and the region necessary for replication of pSMI. Analysis of these plasmids, named pBV plasmids, with restriction endonucleases and by nucleotide sequencing allowed us to determine regions necessary or unnecessary for replication, thus defining a minimal replication region of pSMI. The present method is generally useful for the isolation of small derivatives from any large plasmid for the study of genes and sites adjacent to or within the minimal replication region of the plasmid. 相似文献
85.
Y.-S. Teng 《Biochemical genetics》1981,19(1-2):107-114
Two separate human liver aldehyde dehydrogenases exist which show differences in substrate specificity, cation inhibition or activation, and molecular weight. In this paper we report a common absence of enzyme 2 in Chinese which may be taken to indicate a gene deletion coding for this enzyme. The possible implication of this gene deletion among Chinese is discussed. 相似文献
86.
The locus for sorbitol dehydrogenase (SORD, E.C. 1.1.1.14) has been shown to segregate with hexosaminidase A and mannose phosphate isomerase in a series of human-Chinese hamster somatic cell hybrids. Cytogenetic analysis supports the assignment to chromosome 15 and further defines the gene locus to the region 15pterq21.This research was supported by the Medical Research Council of Canada (MT 4061), the Children's Hospital of Winnipeg Research Foundation, Inc., and the Department of Health, Province of Manitoba (H.S.W.). 相似文献
87.
R. B. Cumming Marva F. Walton J. C. Fuscoe B. A. Taylor J. E. Womack F. H. Gaertner 《Biochemical genetics》1979,17(5-6):415-431
A single formamidase, which is different from the formamidases found in other tissues, occurs in the brains of mice. This enzyme is here called formamidase-5 and the gene symbol is designated For-5. Two alleles are recognized on the basis of their differential heat sensitivity: For-5
b is relatively heat stable and is present in strain C57BL/6J, while For-5
d is relatively heat sensitive and is present in strain DBA/2J. The heat sensitivity of formamidase-5 in 44 other inbred strains and substrains was tested and found to resemble that of C57BL/6J or DBA/2J. Thirty-six recombinant inbred strains derived from progenitors that differed at For-5 were studied to test for single-gene inheritance and linkage with other loci. Complete concordance was found with the esterase-10 locus (Es-10), indicating close linkage. The 99% upper confidence limit of the distance between For-5 and Es-10 is 3.7 centimorgans (cM). Es-10 is located on chromosome 14 about 19 cM from the centromere. An independent demonstration of linkage of For-5 with Es-10 and another chromosome 14 marker, hairless (hr), is provided by the finding that the HRS/J strain, which has been sibmated for 60 generations with forced heterozygosity at the hr locus, is cosegregating at For-5 and Es-10. A survey of 32 inbred strains and substrains revealed that the For-5
d allele is associated with the Es-10
b allele, and that the For-5
b allele is associated with Es-10
a and Es-10
c. Formamidase-5 segregates as expected in the F2 generation of crosses between strains bearing For-5
b and For-5
d alleles. It is possible that this unique formamidase of the brain is involved in the metabolism of a neurotransmitter substance.This research was sponsored in part by the Department of Energy under contract with the Union Carbide Corporation and in part by NIH Research Grant GM-18684 from the National Institute of General Medical Sciences. J. C. F. is a predoctoral Fellow supported by Grant CA 09104 from the National Cancer Institute. The Biology Division of Oak Ridge National Laboratory and the Jackson Laboratory are fully accredited by the American Association for Accreditation of Laboratory Animal Care. 相似文献
88.
89.
Thomas D. Lewin Ali A. Fouladi-Nashta Peter W.H. Holland 《Molecular biology and evolution》2022,39(5)
Eutherian Totipotent Cell Homeobox (ETCHbox) genes are mammalian-specific PRD-class homeobox genes with conserved expression in the preimplantation embryo but fast-evolving and highly divergent sequences. Here, we exploit an ectopic expression approach to examine the role of bovine ETCHbox genes and show that ARGFX and LEUTX homeodomain proteins upregulate genes normally expressed in the blastocyst; the identities of the regulated genes suggest that, in vivo, the ETCHbox genes play a role in coordinating the physical formation of the blastocyst structure. Both genes also downregulate genes expressed earlier during development and genes associated with an undifferentiated cell state, possibly via the JAK/STAT pathway. We find evidence that bovine ARGFX and LEUTX have overlapping functions, in contrast to their antagonistic roles in humans. Finally, we characterize a mutant bovine ARGFX allele which eliminates the homeodomain and show that homozygous mutants are viable. These data support the hypothesis of functional overlap between ETCHbox genes within a species, roles for ETCHbox genes in blastocyst formation and the change of their functions over evolutionary time. 相似文献
90.
Etimad Huwait Sanaa Almowallad Rehab Al-Massabi Salma Saddeek Kalamegam Gauthaman Alexandre Prola 《Current issues in molecular biology》2022,44(5):2153
Atherosclerosis is an important cause of cardiovascular disorders worldwide. Natural botanical drugs have attracted attention due to their antioxidant, anti-inflammatory, and antiatherogenic properties in the treatment of atherosclerosis. Punicalagin is the major bioactive component of pomegranate peel, and has been shown to have antioxidant, anti-inflammatory, antiviral, anti proliferation, and anticancer properties. To explore its antiatherogenic properties at a molecular level, we investigated the genome-wide expression changes that occur in differentiated THP1 cells following treatment with a non-toxic dose of punicalagin. We also conducted a molecular docking simulation study to identify the molecular targets of punicalagin. 相似文献