Forgot your password?
New user?
New Window Opens on the Secret Life of Microbes: Scientists Develop First Microbial Profiles of Ecosystems
CAS announces the release of SciFinder Scholar for Mac OS X
Press Releases
Press Releases
| Check out our New Publishers' Select for Free Articles |
Biochemical Genetics (v.42, #5-6)
Molecular Phylogeny of the Genus Paramesotriton (Caudata: Salamandridae) by Shunqing Lu; Zhi-Gang Yuan; Junfeng Pang; Datong Yang; Fahong Yu; Peter McGuire; Feng Xie; Ya-Ping Zhang (pp. 139-148).
To elucidate the phylogeny of the genus Paramesotriton (Caudata: Salamandridae), we investigated three mitochondrial DNA gene fragments (1207 bp in total) of cytochrome b, ND2, and ND4 for its six recognized species. The phylogenetic relationships within Paramesotriton were reconstructed by maximum parsimony (MP) and maximum likelihood (ML) methods. Phylogenetic trees (MP and ML trees) that were constructed from the combined data set of the three gene fragments indicated that all six species of Paramesotriton formed a monophyletic group, with P. caudopunctatus as basal to the other five species. This result suggests that P. fuzhongensis is a valid species in Paramesotriton.
Keywords: phylogeny; mitochondrial DNA; Paramesotriton
Species-Specific Allozyme Markers for Appalachian Wood-Feeding Cockroaches (Dictyoptera: Cryptocercidae) by Benjamin T. Aldrich; Elliot Krafsur; Srinivas Kambhampati (pp. 149-164).
Members of the genus Cryptocercus are wood-feeding cockroaches that live in the temperate forests. Nine species are recognized in the genus worldwide: two in eastern Eurasia, two in China, and five in the United States. Within the United States, one species occurs in the Pacific Northwest and four occur in the Appalachian Mountains. Previous studies have revealed the presence of potential zones of overlap in distribution among the Appalachian species, raising the possibility of hybridization among them. Differences in mitochondrial DNA have previously been identified for the Appalachian species. However, to identify hybrid individuals one or more species-specific, codominant nuclear markers are required. Therefore, our objective was to undertake allozyme analysis of enzymatic loci to identify fixed, species-specific alleles for the four Appalachian species. We assayed a mean of 42 individuals each from 16 sites for allozyme variation for the four species. At 6 of the 33 loci examined, fixed alternate alleles were identified; a combination of 2 loci enabled the identification of all four species. To identify hybrids in the field, we examined 42 individuals each from 13 sites in which two or more of the above species occur in close proximity for presence of heterozygous individuals at one or more of the six fixed loci. No heterozygous individuals were found suggesting the lack of hybridization among the Appalachian species.
Keywords: Cryptocercus ; allozymes; species-specific markers; mitochondrial DNA
Identification of Amylase Inhibitor Deficient Mutants in Pigeonpea (Cajanus cajan (L.) Millisp.) by N. P. Chougule; A. P. Giri; V. K. Hivrale; P. J. Chhabda; M. S. Kachole (pp. 165-180).
We have developed and analyzed several mutant lines (M6 generation) of pigeonpea (Cajanus cajan (L.) Millsp.) for the content of defensive proteins and antinutritional factors. Inhibitors of proteinase and of amylase, lectins, and raffinose family oligosaccharides were analyzed in mature seeds of different pigeonpea accessions (untreated) and compared with mutant lines. Proteinase inhibitor profiles were similar in terms of number and intensities of activity bands but they differ marginally in the activity units in pigeonpea accessions and mutants. Pigeonpea mutants showed significant differences in amylase inhibitor profiles as well as activity units from those of pigeonpea accessions. Interestingly, two mutants (A6-5-1 and A7-3-2) were identified to have absence of amylase inhibitor isoforms. Hemagglutinating activity and raffinose family oligosaccharides content were found to be significantly higher in mutants than in accessions. It is evident from the results that proteinase inhibitors of pigeonpea are stable while amylase inhibitors, lectins, and raffinose family oligosaccharides show altered expression upon mutagen treatments. These mutants will be ideal candidates for further evaluation.
Keywords: pigeonpea; mutants; proteinase inhibitors; amylase inhibitors; lectins; raffinose family oligosaccharides
Polymorphisms in Blood Proteins of Bos indicus and Bos taurus Cattle Breeds of Cameroon and Nigeria, and Description of New Albumin Variants by E. M. Ibeagha-Awemu; S. Jäger; G. Erhardt (pp. 181-197).
Polymorphisms in the five blood protein loci albumin (ALB), carbonic anhydrase (CA II), vitamin D binding protein (GC), haemoglobin (HBB), and transferrin (TF) were investigated in 520 individuals from 12 cattle populations (Bos indicus and Bos taurus) in Cameroon and Nigeria by isoelectric focusing with carrier ampholytes in ultrathin polyacrylamide gels (PAG-IEF) and by linear gradient polyacrylamide gel electrophoresis (PAGE). While all loci in nine populations were polymorphic with up to six alleles at the ALB and TF loci: the Namchi population showed monomorphism at the CA II locus and Muturu at the ALB, CA II, and HBB loci. There was a clear distinction between Bos indicus and Bos taurus breeds at the ALB locus with ALB B predominating in indicine and ALB A predominating in taurine breeds. CA II S, GC A, and HBB A were the most commonly occurring alleles in all populations. Two variants not described before were demonstrated by PAG-IEF at the ALB locus and named ALB J and ALB K. Mean effective number of alleles as measure of intrabreed diversity was higher in zebu populations (2.040–2.288) as compared to taurine breeds (1.349–1.836). Significant deviations from Hardy–Weinberg equilibrium occurred in some populations at the HBB and TF loci. More haplotypes of ALB/GC occurred in the zebu than taurine breeds. ALB A GC A predominated in the taurine populations and ALB B GC A in the indicine populations. Influence of zebu genes on the Namchi and N'Dama taurine breeds was detected at the ALB, CA II, HBB, and TF loci, and estimated at 61.5% and 5.7%, respectively. The high resolution of PAG-IEF in screening for polymorphisms within diversity studies was demonstrated.
Keywords: polymorphism; blood proteins; haplotype; cattle; Bos taurus ; Bos indicus
Distinct Genes Produce the Alcohol Dehydrogenases of Pollen and Maternal Tissues in Petunia hybrida by Frey Garabagi; Judith Strommer (pp. 199-208).
Analysis of cDNA clones derived from hypoxic root mRNA of Petunia hybrida has revealed the existence of a third active gene encoding alcohol dehydrogenase in petunia. A combination of RT-PCR and ADH activity gels provide evidence for the selective tissue-specific expression of these three genes in multiple floral organs and hypoxically stressed roots. Expression of adh 1 in the plant appears to be restricted to immature pollen grains; the other two genes are expressed differentially in maternal anther tissues, stigma, petals, and hypoxic root. This work underscores the utility of RT-PCR for distinguishing expression patterns of closely related genes, clarifies the expression patterns exhibited by members of this gene family, and suggests multiple functions for the adh genes of petunia.
Keywords: alcohol dehydrogenase; petunia; gene family; adh3
Note: A PCR-Based Analysis of Hox Genes in an Earthworm, Eisenia andrei (Annelida: Oligochaeta)
by Pyo Yun Cho; Sung Jin Cho; Myung Sik Lee; Jong Ae Lee; Eun Sik Tak; Chuog Shin; Jong Kil Choo; Soon Cheol Park; Kyu-Seok Lee; Ho-Yong Park; Chang-Bae Kim (pp. 209-216).