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71.
Contrasting population structure from nuclear intron sequences and mtDNA of humpback whales 总被引:21,自引:4,他引:21
Powerful analyses of population structure require information from multiple
genetic loci. To help develop a molecular toolbox for obtaining this
information, we have designed universal oligonucleotide primers that span
conserved intron-exon junctions in a wide variety of animal phyla. We test
the utility of exon-primed, intron-crossing amplifications by analyzing the
variability of actin intron sequences from humpback, blue, and bowhead
whales and comparing the results with mitochondrial DNA (mtDNA) haplotype
data. Humpback actin introns fall into two major clades that exist in
different frequencies in different oceanic populations. It is surprising
that Hawaii and California populations, which are very distinct in mtDNAs,
are similar in actin intron alleles. This discrepancy between mtDNA and
nuclear DNA results may be due either to differences in genetic drift in
mitochondrial and nuclear genes or to preferential movement of males, which
do not transmit mtDNA to offspring, between separate breeding grounds.
Opposing mtDNA and nuclear DNA results can help clarify otherwise hidden
patterns of structure in natural populations.
相似文献
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In this preliminary study defense behaviour patterns (fear responses) are described in two closely related, behaviourally different inbred labyrinth fish subspecies and in their F1 generation. The subspecies M. opercularis (characterized briefly by “active escape”) and M. opercularis concolor (characterized by “passive escape”) showed specific differences in the manifestation of certain defense behaviour patterns. In the F1 hybrid generation dominance and overdominance of M. opercularis was found in most defense behaviour patterns. Analysing the frequencies and sequences of movement patterns it could be shown that defensive behaviour is not a random or entirely “plastic” process but that there is sequential linkage between the patterns and they form characteristic clusters. Our results suggest that manifestations of different patterns are under genetic control and presumably, genetic determination of certain patterns is not very complex. Attempts were made to determine whole brain noradrenaline, serotonine and dopamine levels of the two subspecies and a significant difference was found in the noradrenaline content. 相似文献
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Tajchman K. Sawicka-Zugaj W. Greguła-Kania M. Drozd L. Czyżowski P. 《Russian Journal of Genetics》2019,55(12):1506-1513
Russian Journal of Genetics - The red deer (Cervus elaphus) has been translocated across Europe, including Poland in order to improve the quality of local populations of the animal. The aim of the... 相似文献
77.
The water quality of the Siluko River, Edo State, Nigeria was investigated from March to August 2015 to determine its suitability for drinking and usage for domestic purposes. Water samples collected from three stations were tested for thirteen physico-chemical parameters using standard analytical procedures. Temperature, phosphate and chloride were significantly different across the three stations. All other parameters, with the exception of turbidity, dissolved oxygen and phosphate, were within the permissible limits recommended by the Nigerian Standard for Drinking Water Quality (NSDWQ) and World Health Organization (WHO). Water Quality Index (WQI) values ranged from 11.24 to 16.15, indicating excellent water quality. While the quality of the water from the Siluko River is suitable for drinking and domestic usage, to prevent future deterioration of the water, it is recommended that the regulating authorities monitor effluents discharged into the river from human activities. 相似文献
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MS Nandhu Jes Paul Korah P Kuruvilla Anitha Malat Chinthu Romeo CS Paulose 《Journal of biomedical science》2011,18(1):5
Parkinson's disease is characterized by progressive cell death in the substantia nigra pars compacta, which leads to dopamine
depletion in the striatum and indirectly to cortical dysfunction. Increased glutamatergic transmission in the basal ganglia
is implicated in the pathophysiology of Parkinson's disease and glutamate receptor mediated excitotoxicity has been suggested
to be one of the possible causes of the neuronal degeneration. In the present study, the effects of serotonin, gamma-aminobutyric
acid and bone marrow cells infused intranigrally to substantia nigra individually and in combination on unilateral 6-hydroxydopamine
induced Parkinson's rat model was analyzed. Scatchard analysis of total glutamate and NMDA receptor binding parameters showed
a significant increase in Bmax (P < 0.001) in the cerebral cortex of 6-hydroxydopamine infused rat compared to control. Real Time PCR amplification of NMDA2B,
mGluR5, bax, and ubiquitin carboxy-terminal hydrolase were up regulated in cerebral cortex of 6-hydroxydopamine infused rats
compared to control. Gene expression studies of GLAST, ά-Synuclien and Cyclic AMP response element-binding protein showed
a significant (P < 0.001) down regulation in 6-OHDA infused rats compared to control. Behavioural studies were carried out
to confirm the biochemical and molecular studies. Serotonin and GABA along with bone marrow cells in combination showed reversal
of glutamate receptors and behaviour abnormality shown in the Parkinson's rat model. The therapeutic significance in Parkinson's
disease is of prominence. 相似文献
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