The prevalence and recurrence of polyploidization in plant species make it one of the most important evolutionary events in plants, and as a result, polyploidization is an extensively investigated research field. Due ...The prevalence and recurrence of polyploidization in plant species make it one of the most important evolutionary events in plants, and as a result, polyploidization is an extensively investigated research field. Due to the rapid development of sequencing technologies, there is increased evidence to support that polyploidization plays an important role in the diversification of plant species, evolution of genes, and the domestication of crops. Here, we reviewed the influence of polyploidization on various aspects of plant evolution, mainly focused on polyploid origin, characteristics, subsequent genome divergence, and its impact on gene function innovation and crop domestication. The occurrence of many independent polyploidization events in plants was found to be tightly associated with the timing of extreme climate events or natural disasters on earth, leading to mass extinction while possibly facilitating increased polyploidization. Following allo-polyploidization, a distinct phenomenon known as sub-genome dominance occurred during sub-genome evolution, which was found to be associated with the methylation of transposons. Extensive gene fractionations(lost) following polyploidization were reported in almost all paleo-polyploids, and the evolutionary fates of multi-copy genes, such as sub-/neo-functionalization, were further proposed to illustrate their underlying mechanisms. Moreover,polyploidization was found to significantly impact species diversification, with subsequent effects on crop domestication and the development of traits with agronomic importance. Based on the progress of plant polyploidization studies, we discussed several main topics that might further improve our understanding of polyploid evolution and that are likely contribute to the application of polyploidization in crop breeding in the near future.展开更多
Goats are one of the oldest domesticated animal species widely distributed in the world playing an important role in the food production system in Sub-Saharan African Region (SSAR). Due to their multiple uses (milk pr...Goats are one of the oldest domesticated animal species widely distributed in the world playing an important role in the food production system in Sub-Saharan African Region (SSAR). Due to their multiple uses (milk production, meat, fiber and hides) and adaptation aptitudes to ecological conditions, goats produce and contribute positively to farmers’ socio-economy status in various production systems. This review aimed at giving a summary overview on the goat’s production systems characteristics, the genetic diversity and the candidate genes affecting reproductive and milk production performances in goat breeds in SSAR. It has been observed that traditional livestock production system with communal grazing system is the most used in goat keeping in SSAR. The geographical locations play an important role in the relationships between goat’s distributions in the region. At the same time, goats might have been differentiated and isolated one to others due to the wide geographic range, the diversify climate and the topography in the region. Among the six worldwide known haplogroups of goat (A, B, C, D, G and F), haplogroup A is the most representative in SSAR. However, haplogroup G and B can be found in some goat populations in some countries in east (Kenya and Ethiopia) and south parts of Africa. This review reveals that little is known on the candidate genes associated with prolificacy and milk production traits in indigenous goat breeds in the region. That observation suggests the importance of assessing candidate genes associated with economic traits in the populations of goat in SSAR.展开更多
The evolutionarily conserved RNA Polymerase Ⅱ Rpb4/7 sub-complex has been thoroughly studied in yeast and impacts gene expression at multiple levels including transcription,mRNA processing and decay.In addition Rpb4/...The evolutionarily conserved RNA Polymerase Ⅱ Rpb4/7 sub-complex has been thoroughly studied in yeast and impacts gene expression at multiple levels including transcription,mRNA processing and decay.In addition Rpb4/7 exerts differential effects on gene expression in yeast and Rpb4 is not obligatory for yeast(S.cerevisiae)survival.Specialised roles for human(hs)Rpb4/7 have not been extensively described and we have probed this question by depleting hsRpb4/7 in established human cell lines using RNA interference.We find that Rpb4/7 protein levels are inter-dependent and accordingly,the functional effects of depleting either protein are co-incident.hsRpb4/7 exhibits gene-specific effects and cells initially remain viable upon hsRpb4/7 depletion.However prolonged hsRpb4/7 depletion is cytotoxic in the range of cell lines tested.Protracted cell death occurs by an unknown mechanism and in some cases is accompanied by a pronounced elongated cell morphology.In conclusion we provide evidence for a gene-specific role of hsRpb4/7 in human cell viability.展开更多
Objective To investigate the expression of human telomerase catalytic subunit,hTERT, in human non-small cell lung cancer (NSCLC) and its correlations to c-myc gene.Methods hTERT and c-myc mRNA expressions were detecte...Objective To investigate the expression of human telomerase catalytic subunit,hTERT, in human non-small cell lung cancer (NSCLC) and its correlations to c-myc gene.Methods hTERT and c-myc mRNA expressions were detected by semiquantitative reverse transcription-polymerase chain reaction (RT-PCR). Statistical correlation analysis was made to estimate whether there was interrelation between them.Results Positive rate of hTERT expression in 51 surgically resected lung cancer specimens was 86.3%,significantly higher than that in adjacent non-neoplastic lung tissues and benign lesions,which were 14.3% and 27.3% respectively. No statistical significance was observed between the frequency of hTERT expression and histologic types,degree of differentiation,TNM stages,tumor size or lymph nodes metastases. Correlation analysis revealed that the expression of c-myc gene was significantly related to that of hTERT (correlation coefficient,r =0.633,P <0.001).Conclusions hTERT may be a useful tumor marker in diagnosing lung cancer. Significant correlation between the expression of hTERT and c-myc mRNA indicates that the activation and up-regulation of hTERT might be conferred by over-expression of c-myc gene.展开更多
基金supported by the National Key Research and Development Program of China(Grant No.2016YFD0100307 and 2018YFD1000800)the National Natural Science Foundation of China(Grant No.31722048 and 31630068)+1 种基金the Science and Technology Innovation Program of the Chinese Academy of Agricultural Sciencesthe Key Laboratory of Biology and Genetic Improvement of Horticultural Crops,Ministry of Agriculture,P.R.China。
文摘The prevalence and recurrence of polyploidization in plant species make it one of the most important evolutionary events in plants, and as a result, polyploidization is an extensively investigated research field. Due to the rapid development of sequencing technologies, there is increased evidence to support that polyploidization plays an important role in the diversification of plant species, evolution of genes, and the domestication of crops. Here, we reviewed the influence of polyploidization on various aspects of plant evolution, mainly focused on polyploid origin, characteristics, subsequent genome divergence, and its impact on gene function innovation and crop domestication. The occurrence of many independent polyploidization events in plants was found to be tightly associated with the timing of extreme climate events or natural disasters on earth, leading to mass extinction while possibly facilitating increased polyploidization. Following allo-polyploidization, a distinct phenomenon known as sub-genome dominance occurred during sub-genome evolution, which was found to be associated with the methylation of transposons. Extensive gene fractionations(lost) following polyploidization were reported in almost all paleo-polyploids, and the evolutionary fates of multi-copy genes, such as sub-/neo-functionalization, were further proposed to illustrate their underlying mechanisms. Moreover,polyploidization was found to significantly impact species diversification, with subsequent effects on crop domestication and the development of traits with agronomic importance. Based on the progress of plant polyploidization studies, we discussed several main topics that might further improve our understanding of polyploid evolution and that are likely contribute to the application of polyploidization in crop breeding in the near future.
文摘Goats are one of the oldest domesticated animal species widely distributed in the world playing an important role in the food production system in Sub-Saharan African Region (SSAR). Due to their multiple uses (milk production, meat, fiber and hides) and adaptation aptitudes to ecological conditions, goats produce and contribute positively to farmers’ socio-economy status in various production systems. This review aimed at giving a summary overview on the goat’s production systems characteristics, the genetic diversity and the candidate genes affecting reproductive and milk production performances in goat breeds in SSAR. It has been observed that traditional livestock production system with communal grazing system is the most used in goat keeping in SSAR. The geographical locations play an important role in the relationships between goat’s distributions in the region. At the same time, goats might have been differentiated and isolated one to others due to the wide geographic range, the diversify climate and the topography in the region. Among the six worldwide known haplogroups of goat (A, B, C, D, G and F), haplogroup A is the most representative in SSAR. However, haplogroup G and B can be found in some goat populations in some countries in east (Kenya and Ethiopia) and south parts of Africa. This review reveals that little is known on the candidate genes associated with prolificacy and milk production traits in indigenous goat breeds in the region. That observation suggests the importance of assessing candidate genes associated with economic traits in the populations of goat in SSAR.
基金funded by Hong Kong Government Research Grants Council(Project No:HKUST 6412/06M)to K.A.W.Lee.
文摘The evolutionarily conserved RNA Polymerase Ⅱ Rpb4/7 sub-complex has been thoroughly studied in yeast and impacts gene expression at multiple levels including transcription,mRNA processing and decay.In addition Rpb4/7 exerts differential effects on gene expression in yeast and Rpb4 is not obligatory for yeast(S.cerevisiae)survival.Specialised roles for human(hs)Rpb4/7 have not been extensively described and we have probed this question by depleting hsRpb4/7 in established human cell lines using RNA interference.We find that Rpb4/7 protein levels are inter-dependent and accordingly,the functional effects of depleting either protein are co-incident.hsRpb4/7 exhibits gene-specific effects and cells initially remain viable upon hsRpb4/7 depletion.However prolonged hsRpb4/7 depletion is cytotoxic in the range of cell lines tested.Protracted cell death occurs by an unknown mechanism and in some cases is accompanied by a pronounced elongated cell morphology.In conclusion we provide evidence for a gene-specific role of hsRpb4/7 in human cell viability.
文摘Objective To investigate the expression of human telomerase catalytic subunit,hTERT, in human non-small cell lung cancer (NSCLC) and its correlations to c-myc gene.Methods hTERT and c-myc mRNA expressions were detected by semiquantitative reverse transcription-polymerase chain reaction (RT-PCR). Statistical correlation analysis was made to estimate whether there was interrelation between them.Results Positive rate of hTERT expression in 51 surgically resected lung cancer specimens was 86.3%,significantly higher than that in adjacent non-neoplastic lung tissues and benign lesions,which were 14.3% and 27.3% respectively. No statistical significance was observed between the frequency of hTERT expression and histologic types,degree of differentiation,TNM stages,tumor size or lymph nodes metastases. Correlation analysis revealed that the expression of c-myc gene was significantly related to that of hTERT (correlation coefficient,r =0.633,P <0.001).Conclusions hTERT may be a useful tumor marker in diagnosing lung cancer. Significant correlation between the expression of hTERT and c-myc mRNA indicates that the activation and up-regulation of hTERT might be conferred by over-expression of c-myc gene.
