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New Window Opens on the Secret Life of Microbes: Scientists Develop First Microbial Profiles of Ecosystems
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Biochemical Genetics (v.43, #9-10)
A LINE-1 Element Insertion in the 5′-Noncoding Region of Caprine Growth Hormone Receptor Gene
by Andrzej Maj; Lech Zwierzchowski (pp. 465-470).
Allozyme Variability and Phylogenetic Relationships in Honey Bee (Hymenoptera: Apidae: Apis mellifera) Populations From Greece and Cyprus by M. Bouga; G. Kilias; P. C. Harizanis; V. Papasotiropoulos; S. Alahiotis (pp. 471-483).
Ten gene enzymic systems (α-GPDH, AO, MDH, ADH, LAP, SOD, ALP, ACPH, ME, and EST), corresponding to 12 genetic loci, were assayed from five Greek populations representing three subspecies of Apis mellifera, A. m. cecropia (Pthiotida, Kythira), A. m. macedonica (Macedonia), and the “Aegean race” of A. mellifera, which is supposed to be very similar to A. m. adami (Ikaria, Kasos), as well as a population from Cypus (A. m. cypria). ADH∗-1, ADH∗-2, and LAP∗ electrophoretic patterns discriminate the Cyprus population from the Greek populations. MDH∗-1, EST∗-3, SOD∗, ALP∗, and ME∗ loci were found to be polymorphic in almost all populations. The observed heterozygosity was found to range from 0.066 to 0.251. Allele frequencies of all loci were used to estimate Nei's genetic distance, which was found to range between 0.011 and 0.413 among the populations studied. UPGMA and neighbor-joining phylogenetic trees obtained by genetic distance matrix methods, as well as a Wagner tree based on the discrete character parsimony method, support the hypothesis that the most distant population is that from Cyprus. Our allozymic data support A. m. cypria as a distinct subspecies, but there was no allozymic support for the distinction of the other subspecies existing in Greece.
Keywords: Apis melliferagenetic structure; allozymes; phylogenetic relationships; Greece; Cyprus
Analysis of Genetic Variation in Agerolese Cattle Breed
by S. Sartore; V. Barbieri; R. Rasero; P. Sacchi; L. Di Stasio; G. Sartore (pp. 485-490).
Structure and Polymorphism Analysis of Transforming Growth Factor Beta Receptor 1 (TGFBR1) in Pigs by Shin-ichi Shimanuki; Ayumi Mikawa; Yuko Miyake; Noriyuki Hamasima; Satoshi Mikawa; Takashi Awata (pp. 491-500).
Many quantitative trait loci (QTL) for growth and reproductive traits have been detected on the porcine chromosome region 1qter (SSC1qter), making it one of the most important genomic regions for pig breeding. SSC1q corresponds to human chromosome 9, on which lies transforming growth factor beta receptor 1 (TGFBR1). We cloned the porcine TGFBR1 cDNA and gene (as a candidate for QTL) and analyzed the gene structure and polymorphism. Porcine TGFBR1 consists of 9 exons and 8 introns. Intron 2 is alternatively spliced at the acceptor site, resulting in two kinds of mRNA, with putative open reading frames of 1500 and 1512 bp in length. The shorter one encodes 499 amino acid residues. The amino acid sequence has 96.2 and 97.2% sequence similarity to those of human and bovine TGFBR1, respectively. The sequence similarity between porcine and murine TGFBR1 is 95.6%. We detected three single-nucleotide substitutions in exons 1, 2, and 7. Those in exons 1 and 7 are nonsynonymous substitutions resulting in Pro8Ser and Ile413Val substitutions, respectively.
Keywords: TGFBR1Sus scrofasingle nucleotide polymorphism; chromosome 1
Leukemia Inhibitory Factor in Follicular Fluid Is Not Related to the Number and Quality of Embryos as Well as Implantation and Pregnancy Rates
by Yao-Yuan Hsieh; Chi-Chen Chang; Horng-Der Tsai; Chich-Sheng Lin (pp. 501-506).
Phylogeny and Molecular Evolution of Tetraogallus in China by Ruan Luzhang; Zhang Lixun; Wen Longying; Sun Qingwei; Liu Naifa (pp. 507-518).
In total, 535 nucleotides in the mtDNA cytochrome b have been sequenced in Tetraogallus. The 53 variable sites define 16 haplotypes in 53 Tetraogallus himalayensis samples, 1 haplotype in 2 T. altaicus samples, and 6 haplotypes in 19 T. tibetanus samples. The lowest genetic distance is between T. himalayensis and T. altaicus (0.011). The divergent time is 0.69 Ma BP between T. himalayensis and T. altaicus, 4.06 Ma BP between T. himalayensis and T. tibetanus, and 4.19 Ma BP between T. altaicus and T. tibetanus. The evidence of this work showed that T. altaicus should fall under the dark-bellied group of Tetraogallus. The dark-bellied and white-bellied speciation first occurred along with the uplift of the Qinghai-Tibet Plateau. A maximum glacier (0.80–0.60 Ma BP) led to the formation of T. altaicus.
Keywords: cytochrome bgenetic distance; Qinghai-Tibet Plateau; white-bellied group; dark-bellied group
Genetic Heterogeneity in Trypanosoma cruzi Strains From Naturally Infected Triatomine Vectors in Northeastern Brazil: Epidemiological Implications by Raquel S. Pacheco; Célia M. Marques de Brito; Otilia Sarquis; Marize Q. Pires; José Borges-Pereira; Marli M. Lima (pp. 519-530).
Eighteen Trypanosoma cruzi strains isolated from naturally infected triatomines were studied genetically. The majority of the strains were from Triatoma brasiliensis, the principal vector of Chagas disease in the northeast of Brazil. Multilocus enzyme electrophoresis (MLEE) and randomly amplified polymorphic DNA (RAPD) analyses were used to investigate the genotypic diversity and the spread of the T. cruzi genotypes in different environments. MLEE clearly distinguished two distinct isoenzyme profiles, and RAPD analysis revealed 10 different genotypes circulating in rural areas. The strains could be typed as isoenzyme variants of the T. cruzi principal zymodeme Z1 (T. cruzi I). An effective program of epidemiological vigilance is required to prevent the spread of T. cruzi I strains into human dwellings.
Keywords: Chagas disease; MLEE; molecular epidemiology; RAPD; triatominesTrypanosoma cruzi
Identification of a Single Nucleotide Polymorphism in Porcine Testis Cytochrome P450-c17 (CYP17) and Its Effect on Steroidogenesis by Zhihong Lin; Yanping Lou; E. James Squires (pp. 531-542).
Raising uncastrated male pigs could have significant economic benefits for pig production. Uncastrated male pigs can accumulate high levels of 16-androstene steroids, however, resulting in boar taint, which is highly objectionable to consumers. Cytochrome P450-c17 (CYP17) interacts with cytochrome b5 in the biosynthesis of the 16-androstene steroids and the sex steroids from pregnenolone. Amino acid substitutions in CYP17 could therefore affect the ability of this enzyme to catalyze the reactions leading to the production of androstenone and the sex steroids. In this study, we established a sensitive and flexible single-stranded conformational polymorphism technique capable of detecting a single nucleotide polymorphism. We then used this method to identify a substitution from T to A at nucleotide 1317 of CYP17, which caused a change in the amino acid sequence from Leu439 to His439. This mutation, however, did not alter the enzyme activity of CYP17 in the biosynthesis of androstenone or sex steroids. Other polymorphisms previously suggested for CYP17, which are vital for the functional interaction of CYP17 with CYB5 in human, were not observed. This study suggests that the synthesis of androstenone in pig testis is not directly affected by any polymorphisms in the coding region of the porcine CYP17 gene.
Keywords: cytochrome P450-c17 (CYP17); 16-androstene; PCR-SSCP; polymorphism; mutation
Polymorphisms of DNA Repair Genes: ERCC1 G19007A and ERCC2/XPD C22541A in a Northeastern Chinese Population by Jiaoyang Yin; Jicheng Li; Ulla Vogel; Huiwen Wang (pp. 543-548).
DNA repair systems are responsible for maintaining the integrity of the genome and have a critical role in protecting against mutations that can lead to cancer. DNA repair gene products of ERCC1 and ERCC2/XPD are involved in the nucleotide excision repair pathway. The allele frequencies of the polymorphisms ERCC1 G19007A and ERCC2/XPD C22541A were examined in a northeastern Chinese population. The allele frequencies were 0.21 (A) and 0.79 (G) for ERCC1 G19007A and 0.49 (A) and 0.51 (C) for ERCC2/XPD C22541A. Comparison with average frequencies from previously reported Caucasian studies demonstrated that the A-allele frequency of ERCC1 G19007A was much lower in the northeastern Chinese population, indicating a remarkable ethnic difference (χ(1)2 = 160.09, p < 0.001), and that allele frequencies of ERCC2/XPD C22541A showed marginal racial differences (χ(1)2 = 4.36, p = 0.04). We have previously reported that both homozygote carriers of the A-allele as well as homozygous carriers of a high-risk haplotype (which includes the AA genotype in ERCC1 G19007A) were at increased risk of basal cell carcinoma, breast cancer, and lung cancer among Caucasians. The low A-allele frequency of ERCC1 G19007A in the Chinese population may suggest that the genetic contribution to cancer risk differs substantially between ethnic groups.
Keywords: DNA repair genesERCC1 G19007AERCC2/XPD C22541A; genetic polymorphism; Chinese population
Thermolabile Variant, PHOX-S, of Prophenol Oxidase in Drosophila melanogaster by Nobuhiko Asada; Satoko Kitamura; Mitsuo Tanaka; Shigeo Yamazaki; Masayoshi Namba (pp. 549-560).
The PhoxS strain of Drosophila melanogaster is an electrophoretically slow variant found in a wild population at Victoria, Australia. Prophenol oxidase isoform A1 from PHOX-S was purified and characterized biochemically and genetically. The purified fraction of A1 from PHOX-S showed a homodimer with a molecular weight of the subunit of approximately 77 kDa. The PhoxS strain was temperature sensitive in vivo in culture, and the purified protein was thermolabile in vitro. By the deletion mapping method, the PhoxS locus was cytologically estimated to be at the location 55-A on the right arm of the second chromosome and 79.6 genetically. These data show that PHOX-S is an electrophoretic variant of MOX and that PHOX-S is the first thermolabile protein found in invertebrate prophenol oxidase.
Keywords: phenol oxidase; PHOX-S; thermolabileDrosophila