摘要:

TheDrosophilamemory mutantrutabaga(rut) has been previously shown to have a defective subpopu-lation (or functional state) of the enzyme adenylate cyclase. We report here that the reduced adenylate cyclase activity is also associated with a defective responsiveness of the enzyme to forskolin. Forskolin activation isotherms of the enzyme in normal membranes reveal low- and high-affinity forskolin-interacting components; the residual enzyme in the mutant shows a smaller proportion of the high-affinity response. In addition, in mutant membrane preparations, forskolin fails to shift theKmof the enzyme for free Mg2+and for MgATP, in contrast to the situation in the normal tissue. The defect in the responsiveness to forskolin inrutis even more pronounced in a Lubrol-solubilized enzyme preparation, and is due to intrinsic properties of the cyclase system rather than to the absence (or presence) of a soluble, or detergent solubilized, factor inrut. The reduced forskolin responsiveness maps to the X chromosomal segment 12F5-6 to 13A1-5, within the region previously reported to span the locus that controls both the abortive memory and the lack of Ca2+-stimulation of adenylate cyclase inrut17. The possible relevance of the findings to postulated molecular mechanisms of short-term memory formation is discussed.

ISSN:0167-7063    

DOI:10.3109/01677068509101423

出版商:Taylor&Francis    

年代:1985

数据来源: Taylor

摘要:

Inbred mice of the DBA/2J and C57BL/6J strains are known to differ in physiological and behavioral characteristics that are partially controlled by nuclei in the preoptic area/anterior hypothalamus. We describe a distinguishing nucleus of darkly staining, densely packed cells, which we term the medioventral pars compacta (MVPC), within the medial preoptic nucleus of DBA/2J, but not C57BL/6J mice. The analysis also indicates that this nucleus is nearly 80% larger in volume in females vs males of the DBA/2J strain. The strain difference may be used to define genetic influences on this neuroanatomical and functional property.

ISSN:0167-7063    

DOI:10.3109/01677068509101424

出版商:Taylor&Francis    

年代:1985

数据来源: Taylor

摘要:

A classical cross-breeding study involving the inbred mouse strains DBA/2 and C3H/HeJ revealed a rather complex mode of inheritance for the following hippocampal variables: size of stratum pyramidale, number of supra-, intra- and infrapyramidal mossy fiber synapses, and the size of terminal fields receiving entorhinal input. A polygenic mode of inheritance was inferred for these phenotypes. For the size of the regio inferior a model containing additive genetic effects only was sufficient to explain the variation between generations. The strain difference may be caused by one genetic factor only. In agreement with previous experiments a strong negative correlation between the number of intra- and infrapyramidal mossy fiber synapses and shuttle-box avoidance performance was found in the genetically heterogeneous F2population.

ISSN:0167-7063    

DOI:10.3109/01677068509101425

出版商:Taylor&Francis    

年代:1985

数据来源: Taylor

摘要:

Screening polymorphic DNA probes for linkage to myotonic dystrophy (DM) and to other reported chromosome 19 (CH19) genes will develop a linkage map for human CH19. We report here the assignment of 3 cloned unique DNA sequences to 3 distinct regions of CH19. The novel use of35S-labeled probes facilitated the rapid localization of the gene for the third complement factor (C3) to 19pl3.2 by in situ hybridization. Metaphase chromosomes were from normal peripheral lymphocytes as well as from a fibroblast line containing a 15;19 translocation which permitted clear identification of CH19 regions of localization. Two random clones isolated from a plasmid library of human F-group enriched chromosomal DNA (D19S5 and D19S6) were in like manner assigned to 19pl.2 and 19ql3.2 to 19qter, respectively.

ISSN:0167-7063    

DOI:10.3109/01677068509101426

出版商:Taylor&Francis    

年代:1985

数据来源: Taylor

摘要:

The metabolism of leucine was studied in cultured human fibroblasts derived from patients with defects in each of the major steps in the catabolism of the amino acid. Intact fibroblasts were incubated with [U-14Clleucine and the organic acid products were isolated by liquid partition chromatography. In control fibroblasts the major product of leucine was 3-hydroxyisovaleric acid. This was also the case for fibroblasts with deficiency of 3-hydroxy-3-methylglutaryl-CoA lyase, 3-methylcrotonyl-CoA carboxylase and 3-methyl-glutaconyl-CoA hydratase. There was little or no accumulation of the compound with fibroblasts from patients with maple syrup urine disease and isovaleric acidemia.

ISSN:0167-7063    

DOI:10.3109/01677068509101427

出版商:Taylor&Francis    

年代:1985

数据来源: Taylor