新城疫病毒分子生物学研究现状

本文详尽地介绍了新城疫病毒近几年的研究进展,着重从病原基因组特性、编码蛋白、致病机理以及基因工程活载体苗的研究上做了综合概述,为新城疫病毒的深入研究奠定了基础。     

玉米起源新模式——两类大刍草的融合

作物驯化是人类文明发展史中最为重要的事件之一,推动了人类社会从单纯的狩猎和采集型向农业型的转变。玉米(Zea mays L.)作为世界上最重要的农作物之一,其起源演化的机制一直备受关注。2012年12月1日,华中农业大学严建兵团队与其合作团队在Science(《科学》)在线发表研究论文,通过深入解析大量玉米野生种和栽培种材料的基因组变异,重新定义了现代栽培玉米的驯化过程,揭示了6 000年前墨西哥高原亚种(Zea mays subsp. mexicana)基因组的渗入及其优异等位基因的选择,实现了栽培玉米的二次驯化,同时推动了栽培玉米的广泛传播,研究结果为深入阐明作物起源演化这一古老的科学问题提供了重要的线索。     

Cytogenetic Analysis of the Primary Amphidiploid Derived from Interspecific Hybridization in Cucumis and Its Selfed Progenies

Studies on the reproduction and cytogenetic characterization of a primary amphidiploid Cucumis species C. hytivus Chen and Kirkbride (2n = 4x = 38) indicated that a more comprehensive cytogenetic analysis of this species and its first selfed progeny would increase its potential utility in cucumber improvement. With tendrils used as source materials for mitotic analysis, chromosome numbers in all selfed progenies were 2n = 38, confirming chromosomal stability in this synthetic amphidiploid species. Detailed meiotic processes were described by comparing the primary and the selfed amphidiploids.Meiotic abnormalities, such as chromosome lagging, unequal separation, chromosome multi-polarization and polyads were observed frequently in all amphidiploid plants except for the selfed no.8, in which meiosis was arrested prior to metaphase I. Generally, the frequency of multivalents was higher and the configurations were more complex in the selfed progenies, demonstrating a more extensive genetic exchange between cucumber and C. hystrix Chakr. Genome separation between cucumber and C. hystrix was observed through prophase ! to anaphase I in both generations of the amphidiploids. Consequently, in addition to n = 19, a new gamete with n = 7 was produced, which was confirmed by the chromosome counts 2n = 14 in the backcrossing progenies from cucumber × amphidiploid mating. Fertility varied among the selfed amphidiploid plants. The selfed plant no. 1 was found to have an improved fertility (e.g., pollen staining ability 40.8% and 25.6 seeds per fruit) and then was used as source germplasm in further introgression and gene exchange experiments.     

Genetic Susceptibility to Rhodococcus equi

Rhodococcus equi pneumonia is a major cause of morbidity and mortality in neonatal foals. Much effort has been made to identify preventative measures and new treatments for R. equi with limited success. With a growing focus in the medical community on understanding the genetic basis of disease susceptibility, investigators have begun to evaluate the interaction of the genetics of the foal with R. equi. This review describes past efforts to understand the genetic basis underlying R. equi susceptibility and tolerance. It also highlights the genetic technology available to study horses and describes the use of this technology in investigating R. equi. This review provides readers with a foundational understanding of candidate gene approaches, single nucleotide polymorphism‐based, and copy number variant‐based genome‐wide association studies, and next generation sequencing (both DNA and RNA).     

植物基因组CNV研究进展及其对麦类作物相关研究的启示

拷贝数变异(Copy number variation,CNV)是作物基因组中广泛存在的一种遗传变异,与作物的适应性、抗逆性等许多重要农艺性状相关。本文主要就CNV的发生机制、研究方法,尤其是植物中CNV与表型、CNV与植物适应性进化、CNV与重要农艺性状的关联分析等方面的研究进展进行了概述,并就植物CNV的研究对麦类作物相关研究的启示进行了深入剖析,以期为我国麦类作物开展CNV相关研究提供参考信息。     

结直肠癌基因组流行病学研究进展

基因组流行病学的研究是近年来遗传流行病学与分子流行病学相互融汇交织而发展起来的新兴学科,它是从基因组学研究到医学实践的重要桥梁。全世界范围内,结直肠癌的发病率及死亡率有逐年上升的趋势,因此有必要从基因组流行病学的角度认清结直肠癌的流行病学及分子发病机制。本文重点围绕基因-基因以及基因-环境的交互作用对结直肠癌的影响作一阐述,旨在为结直肠癌基因的靶向治疗提供理论依据。     

番茄基因工程的研究进展

文中概述了近几年来番茄基因工程方面的研究进展。其中番茄基因组精细序列分析的完成是这一领域得以快速发展的基础。在育种方面,利用转基因技术生产出了具有各种抗性的番茄植株,获得了具有优良品质的新品种。同时,基因工程手段拓展了番茄在医学上的应用。目前研究人员已利用番茄生产药用蛋白、抗体、口服疫苗、病毒转基因番茄疫苗,并且对番茄红素的研究有望推动对癌症基因疗法的研究。总之,利用基因工程手段,有望使番茄成为集治疗、营养和免疫于一身的新型蔬菜。     

口蹄疫病毒全基因组序列特征分析

对口蹄疫病毒全基因组序列特征的分析有助于了解口蹄疫病毒复制、翻译等生命活动的相关机制.利用DNAStar和DNAMAN软件,对249株口蹄疫病毒全基因组序列进行了比对分析.结果表明,口蹄疫病毒ORF的长度为5 982～7 020 bp,平均长度为6 975 bp,编码1 994～2 340个氨基酸.各基因的核酸序列同源...     

A novel genome of C and the first autotetraploid species in the <Emphasis Type="Italic">Setaria</Emphasis> genus identified by genomic <Emphasis Type="Italic">in situ</Emphasis> hybridization

Genomic in situ hybridization (GISH) was used to investigate the genomic relationships among some newly collected species of genus Setaria. Previous work identified that S. viridis and S. adhaerens carry genomes A and B, respectively. GISH patterns obtained in this report clearly distinguished the genome of S. grisebachii from the known genomes A and B, and indicated its new genomic constitution which we suggest to name genome C of the Setaria genus. The two sets of chromosomes of tetraploid S. queenslandica hybridized well with the A genome of S. viridis indicating its autotetraploid nature. This is the first autotetraploid identified in the Setaria genus, which should be classified into the primary A genome gene pool rather than the tertiary gene pool as previously classified. GISH patterns did not distinguish the genome of S. leucopila from the A genome of S. viridis and S. italica, suggesting its close relation with foxtail millet. Strong hybridization signals were observed when S. adhaerens genomic DNA was used as probe to hybridize the chromosomes of diploid S. verticillata, inferring its B genome nature. Combined with morphological observation and previous work, we deduce that diploid S. verticillata and S. adhaerens are probably taxonomically the same species with different names. Y. Wang and H. Zhi contributed equally to this article.