Temperature gradient gel electrophoresis: detection of a single base substitution in the cattle β-lactoglobulin gene

An A in equilibrium with G transition in exon III is known to differentiate alleles A and B of the cattle beta-lactoglobulin (BLG) gene. A BLG exon III fragment containing the transition site was amplified by the polymerase chain reaction. Temperature gradient gel electrophoresis (TGGE) was then used to detect this transition and hence to genotype cattle: the AT base-pair in allele A was readily distinguished from the GC base-pair of allele B. TGGE can be used to detect any single base-pair substitution, and thus is a powerful method of detecting genetic variability.     

Advances in endophenotyping schizophrenia

The search for the genetic architecture of schizophrenia has employed multiple, often converging strategies. One such strategy entails the use of tracing the heritability and neurobiology of endophenotypes. Endophenotypes are quantifiable traits not visible to the eye, which are thought to reflect an intermediate place on the path from genes to disorder. Endophenotype abnormalities in domains such as neurophysiology or neurocognition occur in schizophrenia patients as well as their clinically “unaffected” relatives, and reflect polymorphisms in the DNA of schizophrenia spectrum subjects which create vulnerability to developing schizophrenia. By identifying the single nucleotide polymorphisms (SNPs) associated with endophenotypes in schizophrenia, psychiatric neuroscientists can select new strong inference based molecular targets for the treatment of schizophrenia.     

野大豆(Glycine soja)叶绿体的光谱及其激子能量转移

野大豆叶绿体在低温(77K)时出现三条荧光发射谱带,它们来源于不同的色素蛋白复合体。 在纳秒脉冲激光激发下,捕光天线色素的相对荧光量子产额,随激光强度的增加有明显下降现象。用激子理论和动力学方程讨论和计算了激子扩散参量。指出激子转移是随机的,非相干的。     

Responses of atmospheric methane consumption by soils to global climate change

Soils consume about 40 Tg methane from the atmosphere annually. Thus, soils contribute significantly to the atmospheric methane budget. However, responses of atmospheric methane consumption to climate change are uncertain. Predicting these responses requires an understanding of the effect on methane consumption of specific variables (temperature and soil water content) as well as interactions among parameters (methane, ammonium, water content). Key considerations involve the limitations of diffusive transport and controls of methane diffusivity; limitation of methanotrophic activity by water stress; relatively slow growth rates of methane-oxidizing bacteria on atmospheric methane; ammonium toxicity. Interactions among these parameters may be particularly important, and lead to responses contrary to those predicted from changes in temperature and water content alone. Results from a number of analyses indicate that atmospheric methane consumption is especially sensitive to anthropogenic disturbances, which typically decrease activity. Continued increases in wet and dry ammonium deposition are likely to exacerbate inhibition resulting from changes in land use. Changes in hydrological regimes could further decrease activity if dry periods increase water stress at soil depths currently colonized by methanotrophs. Future trends in the soil methane sink are likely to lead to enhanced accumulation of atmospheric methane.