Molecular Relationships Within Australasian Waterfowl (Anseriformes)

1996 ◽  
Vol 44 (1) ◽  
pp. 47 ◽  
Author(s):  
M Sraml ◽  
L Christidis ◽  
S Easteal ◽  
P Horn ◽  
C Collet
Keyword(s):  
Cytochrome B ◽  
Endemic Species ◽  
Base Pair ◽  
Phylogenetic Relationships ◽  
Sequence Variation ◽  
Cytochrome B Gene ◽  
Base Pair Fragment ◽  
Molecular Relationships ◽  
Pair Fragment ◽  
Controversial Nature

Within Australia there are 19 endemic species of Anseriformes. Six of these belong to monotypic genera, some of which remain controversial with respect to phylogenetic relationships. Sequence variation in a 307-base pair fragment of the cytochrome-b gene was compared from 23 species of waterfowl (the Cairina sequence was obtained from the literature) to elucidate further the relationships of these monotypic Australian genera. Anseranas and Dendrocygna were identified as the earliest diverged genera among the taxa examined. The remaining genera fell into two groups: (1) Tadorna, Alopochen, Chenonetta, Anas, Aythya, Cairina and Air and (2) Cygnus, Branta, Cereopsis, Biziura, Oxyura, Malacorhynchus, Stictonetta and Nettapus. The controversial nature of the last group is discussed.

Two systems of glucose repression of the GAL1 promoter in Saccharomyces cerevisiae

1990 ◽  
Vol 10 (9) ◽  
pp. 4757-4769
Author(s):  
J S Flick ◽  
M Johnston
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Base Pair ◽  
Glucose Repression ◽  
Gene Products ◽  
Gal1 Promoter ◽  
Base Pair Fragment ◽  
Common Signal ◽  
Multiple Sequences ◽  
Pair Fragment ◽  
Gal1 Gene

Expression of the GAL1 gene in Saccharomyces cerevisiae is strongly repressed by growth on glucose. We show that two sites within the GAL1 promoter mediate glucose repression. First, glucose inhibits transcription activation by GAL4 protein through UASG. Second, a promoter element, termed URSG, confers glucose repression independently of GAL4. We have localized the URSG sequences responsible for glucose repression to an 87-base-pair fragment located between UASG and the TATA box. Promoters deleted for small (20-base-pair) segments that span this sequence are still subject to glucose repression, suggesting that there are multiple sequences within this region that confer repression. Extended deletions across this region confirm that it contains at least two and possibly three URSG elements. To identify the gene products that confer repression upon UASG and URSG, we have analyzed glucose repression mutants and found that the GAL83, REG1, GRR1, and SSN6 genes are required for repression mediated by both UASG and URSG. In contrast, GAL82 and HXK2 are required only for UASG repression. A mutation designated urr1-1 (URSG repression resistant) was identified that specifically relieves URSG repression without affecting UASG repression. In addition, we observed that the SNF1-encoded protein kinase is essential for derepression of both UASG and URSG. We propose that repression of UASG and URSG is mediated by two independent pathways that respond to a common signal generated by growth on glucose.

scholarly journals Molecular phylogeny of East Asian moles inferred from the sequence variation of the mitochondrial cytochrome b gene.

2000 ◽  
Vol 75 (1) ◽  
pp. 17-24 ◽  
Author(s):  
Kimiyuki Tsuchiya ◽  
Hitoshi Suzuki ◽  
Akio Shinohara ◽  
Masashi Harada ◽  
Shigeharu Wakana ◽  
...  
Keyword(s):  
Molecular Phylogeny ◽  
Cytochrome B ◽  
Sequence Variation ◽  
East Asian ◽  
Cytochrome B Gene ◽  
Mitochondrial Cytochrome ◽  
Mitochondrial Cytochrome B ◽  
Mitochondrial Cytochrome B Gene

Reassessment of Phylogenetic Relationships among Pitviper Genera Based on Mitochondrial Cytochrome b Gene Sequences

Copeia ◽  
1997 ◽  
Vol 1997 (2) ◽  
pp. 429 ◽  
Author(s):  
Kenneth W. Cullings ◽  
David J. Morafka ◽  
José Hernandez ◽  
John W. Roberts ◽  
Jose Hernandez
Keyword(s):  
Cytochrome B ◽  
Phylogenetic Relationships ◽  
Cytochrome B Gene ◽  
Mitochondrial Cytochrome ◽  
Gene Sequences ◽  
Mitochondrial Cytochrome B ◽  
Mitochondrial Cytochrome B Gene

A molecular phylogenetic study of Hylopetes (Rodentia: Sciuridae) inferred from mitochondrial cytochrome-b gene

Biologia ◽  
2014 ◽  
Vol 69 (12) ◽  
Author(s):  
Farong Yu ◽  
Xiuzhen Lian ◽  
Zuoping Li ◽  
Mingren Xie
Keyword(s):  
Cytochrome B ◽  
Phylogenetic Relationships ◽  
Cytochrome B Gene ◽  
Phylogenetic Study ◽  
Molecular Phylogenetic Study ◽  
Mitochondrial Cytochrome B ◽  
Distinct Genus ◽  
Molecular Phylogenetic ◽  
Close Genetic Relationship ◽  
Tectonic Movements

AbstractTo elucidate the phylogenetic relationships of Hylopetes, the complete cytochrome-b gene sequences (1,140 bp) were determined from degraded museum specimens for phylogenetic study. The large genetic differences (18.1% to 20.7%) separate Eoglaucomys from Hylopetes as a distinct genus. Phylogenetic relationships reconstructed with maximum parsimony, maximum likelihood, and Bayesian methods show that all Hylopetes were genetically clustered as two major groups, the Indochinese Hylopetes group including H. alboniger and H. phayrei, and the Sundaic group consisting of H. lepidus, H. nigripes, and H. spadiceus. The close genetic relationship and the recent divergence suggest that the Indochinese group rapidly extended to their present distributions with the uplifting of the Himalayas last few million years ago, whereas the oceanic tectonic movements during the Pliocene-Pleistocene resulted in the current geographical distributions of the Sundaic group through alteration of dispersal across the islands of the Sunda Shelf.

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