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Biochemical Genetics (v.37, #5-6)
Properties of Phenoloxidases Generated from Prophenoloxidase with 2-Propanol and the Natural Activator in Drosophila melanogaster by Nobuhiko Asada; Hiroshi Sezaki (pp. 149-158).
Prophenoloxidases A1 andA3 in Drosophila melanogaster were activatedwith 2-propanol and a partially purified naturalactivator. For prophenoloxidase activation, the optimumtemperaturewas 30 degrees C and the optimum pH was 8. Bothmono- and diphenoloxidase activities were found inA1 and A3 activated with2-propanol, whereas only diphenoloxidase activity wasdetected inA3 activated with a naturalactivator. The kinetic properties, Km and Vmax, were not similar in those phenoloxidasesactivated with different activating agents. The rateof inhibition of phenoloxidase bydiethyldithiocarbamate and phenylthiocarbamate dependedon the concentration of 2-propanol. Both compoundsexhibited a noncompetitive pattern ofinhibition.
Keywords: DROSOPHILA ; PROPHENOLOXIDASE; ACTIVATION; KINETICS
Genetic Diversity of Chinese Native Pigs Inferred from Protein Electrophoresis by Xiaoqiu Wu; Bo Ding; Ya-Ping Zhang (pp. 159-173).
We examined protein polymorphism of 20 nativepig breeds in China and 3 introduced pig breeds. Thirtyloci have been investigated, among which six loci werefound to be polymorphic. Especially, the polymorphismof malate dehydrogenase (MDH), adenylate kinase(AK), and two new alleles of adenosine deaminase (ADA)had not been reported in domestic pigs and wild pigs.The percentage of polymorphic loci (P), the meanheterozygosity (H), and the mean number ofalleles (A) are 0.200, 0.065, and 1.300, respectively.The degree of genetic variability of Chinese pigs as awhole was higher than that of goats, lower than thatof cattle and horses, and similar to that ofsheep. Using the gene frequencies of the 30 loci, Nei'sgenetic distance among the 20 native breeds in China and3 introduced pig breeds was calculated by theformula of Nei. The program NEIGHBOR in PHYLIP3.5c was chosen to construct an UPGMA tree and a NJtree. Our results show that, of the total geneticvariation found in the native pig breeds in China, 31%(0.31) is ascribable to genetic differencesamong breeds. About 69% of the total genetic variationis found within breeds. Most breeds are in linkagedisequilibrium. The patterns of genetic similaritiesbetween the Chinese native pig breeds were notin agreement with the proposed pig type classification.
Keywords: DOMESTIC PIG; PROTEIN ELECTROPHORESIS; GENETIC DIVERSITY
Cloning and Tissue Expressional Characterization of a Full-Length cDNA Encoding Human Neuronal Protein P17.3 by Yingyu Cui; Long Yu; Ruomu Gong; Min Zhang; Yuxin Fan; Peng Yue; Shouyuan Zhao (pp. 175-185).
A full-length cDNA of 595 bp was isolated froma human fetal brain cDNA library. It contains an openreading frame encoding 153 amino acids, with an 18-bp5′UTR and a 118-bp 3′UTR in which there isan atypicalpolyadenylation signal (ATTAAA). The calculatedmolecular weight of the deduced protein is 17.3 kU. Thepredicted isoelectric point is 4.89. On account of itshigh homology to mouse neuronal protein NP15.6(81.2% identity), the deduced protein was namedneuronal protein 17.3 (NP17.3). When its secondarystructure was examined by the GGBSM program of PCGENEsoftware, it was found that 32.6 and 15.0% of itsamino acids are involved in formingalpha-helices and beta-sheets, respectively. Examinedwith the PESTFIND program, a typical PEST region foundin rapidly degraded proteins was found between residue48and residue 68.
Keywords: HUMAN NEURONAL PROTEIN 17.3; MOUSE NP15.6; CDNA CLONING; TISSUE EXPRESSIONAL; CHARACTERIZATION
A Comparison of the Structures of the Alpha:Beta and Alpha:Gamma Dimers of Mouse Salivary Androgen-Binding Protein (ABP) and Their Differential Steroid Bindin by Robert C. Karn; Mark A. Clements (pp. 187-199).
Mouse salivary androgen-binding protein (ABP) isa family of dimeric proteins that may play a pheromonalrole in Mus musculus. The protein dimer consists of acommon alpha subunit disulfide-bonded to avariable (beta or gamma) subunit. Here wereport N-terminal sequences of the beta and gammasubunits, showing that they are very similar to eachother while being quite different from the alphasubunit.We demonstrate differential androgen binding bythe two dimers. Both bind dihydrotestosterone to aboutthe same extent but the alpha:beta dimer bindssignificantly more testosterone than the alpha:gammadimer. We discuss the possible significance ofthis diversity of androgen binding with respect to thepossibility that androgen binding is related to aputative pheromonal role for the protein.
Keywords: SALIVARY ANDROGEN-BINDING PROTEIN; STEROID BINDING; DIMER STRUCTURE; DIHYDROTESTOSTERONE; TESTOSTERONE
Genetic Diversity and Taxonomic Implication of Cordyceps sinensis as Revealed by RAPD Markers by Yongjiu Chen; Ya-Ping Zhang; Yuexiong Yang; Darong Yang (pp. 201-213).
Random amplified polymorphic DNA (RAPD) markersare used to investigate genetic variation andevolutionary relationships of 29 samples of Cordycepssinensis from different geographical populations on theQinghai–Tibet plateau. Out of 137 RAPDbands scored, 100 are polymorphic. A correlation isrevealed between geographical distance and geneticdistance. The molecular phylogenetic tree suggests thatthe 29 samples are divided into three notableclusters, corresponding to the geographical populations,i.e., the north population (NP), middle population (MP),and south population (SP). The NP consists of7 northern samples from Menyuan, Maqu, andLuqu, the MP consists of 8 samples from Yushu andChengduo, and the SP consists of 14 samples from BymaSnow Mountain, Renzhi Snow Moutain, Chongcaoxiwa, andDacaodi.It is demonstrated that extensive geneticdiversity is found among different geographicalpopulations of C. sinensis. The genetic diversitypattern of C. sinensis may be caused by the foundereffects. The taxonomic status of NP, MP, and SP populationsshould be that they are different subspecies rather thandifferent species.
Keywords: CORDYCEPS SINENSIS; GENETIC DIVERSITY; TAXONOMY