条纹斑竹鲨线粒体DNA的研究

用6种限制性内切酶分析了4条条纹斑竹鲨的线粒体DNA(mtDNA)。PstⅠ、Hpa Ⅰ、XbaⅠ、EcoRⅠ、EcoRⅤ、BglⅡ在条纹斑竹鲨mtDNA分子上分别具有0至2个切点, mtDNA分子大小为16.6kb,根据单酶和双酶完全酶解片段的大小,构建了条纹斑竹鲨mtDNA 的限制性酶切图谱。 Abstract:Mitochondrial DNA(mtDNA)form 4 samples of Chiloscyllium plagiosum was analyzed by 6 kinds of restriction.The number of cleavage sites were as follow:2 for HpaI,XbaI and EcoRI respectively;1 for BglII and EcoRV respectively;None for PstI.Molecular size of mtDNA was found to be 16.6kb.According to analysis of single and double enzyme cleavage,the map of restriction enzyme was constructed.     

应用大规模测序技术和生物信息学研究造血干/祖细胞的基因表达及新基因 的识别和克隆

从新生儿脐血和成人骨髓中分选出造血干/祖细胞(HSC/HPC),构建成cDNA文库,对其进行大规模表达序列标签(EST)测序,通过生物信息学等手段分析基因表达谱,并进行新基因的全长cDNA克隆。在所测的10512条可分析E ST序列中,有9866条来自脐血CD34+|细胞,其中4697条(47.6%)为已知基因,2603条(26.4%)为已知EST,1415条(14.3%)代表未知EST。在已知基因中,8.2%基因与造血相关,22.7%涉及细胞代谢、结构和迁移,13.0%与细胞分裂和防御相关,26.2%与RNA、蛋白质的合成相关,10.6%和细胞信号传递有关。对一些已知和未知的EST,综合测序、生物信息学等方法,进行全长克隆,已获得23个新基因的全长cDNA。 Abstract:Hematopoietic stem/progenitor cells were isolated from umbilical cord blood and adult bone marrow,and subject to cDNA library construction.The gene expression pattern in CD34+ cells and the identification and cloning of novel genes were performed by sequencing ESTs and analyzing them with the tools of bioinformatics.Among the obtained 10 512 ESTs which could be further analyzed,9,866 were from umbilical cord blood where 4 697(67.6%)were known genes,2 603(26.4%)were known ESTs and 1415(14.3%)represented novel ESTs.Within the identified genes,8.2% was involved in hematopoiesis,22.7% was associated with cell metabolism,structure and mobility,13.0% was linked to cell division and defence,26.2% was related to RNA protein synthesis and 10.6% was related with cell signal transduction.In parallel,we developed an efficient working system combining sequencing,bioinformatics,etc.and obtained 23 full-length cDNAs from both known and novel ESTs identified in this work.     

用长PCR方法检测含有较大缺失或插入的DNA大片段

选择位于19q13.3上的人类肌张力蛋白激酶基因(myotonin protein kina se gene,MT-PK)为靶基因(基因全长为14kb),以G+C含量较高且含有1kb缺失或插入,由基因第8内含子中的Alu±1kb的5'端至第15外显子3'非编码区中的CTG重复序列3'端,即两者间的距离为5.3kb的DNA片段为待扩增靶序列,通过优化DNA聚合酶的组合和反应缓冲体系,点考查了含有Alu-1k b和Alu+1kb缺失或插入的MT-PK等位基因片段共扩增的长PCR方法。本方法可有效地同步扩增6.5kb和5.5kb两个等位基因片段,对6.5kb和5.5kb纯合等 位片段则达到了更有效的扩增。     

Genetic analysis and mapping of gene fzp(t) controlling spikelet differentiation in rice

A mutant of spikelet differentiation in rice called frizzle panicle (fzp) was discovered in the progeny of a cross between Oryza sativa ssp. indica cv. V20B and cv. Hua1B. The mutant exhibits normal plant morphology but has apparently fewer tillers. The most striking change in fzp is that its spikelet differentiation is completely blocked, with unlimited subsequent rachis branches generated from the positions where spikelets normally develop in wild-type plants. Genetic analysis suggests that fzp is controlled by a single recessive gene, which is temporarily named fzp (t). Based on its mutant phenotype, fzp (t) represents a key gene controlling spikelet differentiation. Some F2 mutant plants derived from various genetic background appeared as the "middle type", suggesting that the action of fzp (t) is influenced by the presence of redundant, modifier or interactive genes. By using simple sequence repeat (SSR) markers and bulked segregant analysis (BSA) method, fzp (t) gene was mapped in the terminal region of the long arm of chromosome 7, with RM172 and RM248 on one side, 3.2 cM and 6.4 cM from fzp (t), and RM18 and RM234 on the other side, 23.1 cM and 26.3 cM from fzp(t), respectively. These results will facilitate the positional cloning and function studies of the gene.     

关于回交世代方差中加性×显性分量的讨论A

当两系统存在k对基因差异,P1中增效基因为k-k’对,减效基因k’对时,两纯系杂交回交群体遗传方差加性×显性分量的数学式为F=(k-k’)∑(i=1)d1h1-k’∑(i=1) d1h1.。F的大小决定于显性齐性和基因分散的程度。因此在一般情况下,F的遗传含义是混杂不清的。只有基因完全相联时F=k∑(i=1)d1h1,与Mather 和Jinks 的推导结果一致,这时F反映显性齐性程度。Abstract: Assuming kpairs of different genes between two pure parental lines (P1 and P2), k-k’ pairs of increasing genes and k’ pairs of deereasing genes in P1,the comoponent of additive×dominance in the genetic variance of the backcross generation is represented as F=(k-k’)∑(i=1)d1h1-k’∑(i=1) d1h1.The component F is determined by both the consistency of dominance and the dispersion of genes. In genetral, the genetic implication of the component F is complexity.Only under the situation of complete associates of genes F=k∑(i=1)d1h1,which agrees with the result by Mather and Jinks. In such case, F illustrates the consistency of dominance.     

中亚林蛙的核型、C带和银带研究及田野林蛙起源的探讨

中亚林蛙（Rana asiatica）的核型为2n=26,NF=52。第2号染色体短臂有一条近端着丝粒区C带。第10号染色体长臂上有一对标准NORs。本文认为,田野林蛙（Rana arvalis）起源于欧洲,是欧洲林蛙群与亚洲2n=24的林蛙群间的过渡种类。The diploid number of Rana asiatica is 2n=26, NF=52,with an acrocetric C-band on 2p and a pair of standard NORs on 10q. The paper holds that Rana arvalis,originated in Europe, is a interim species between Rana group in Europe and Rana group in Asia with 2n=24.     

离体条件下用秋水仙素处理小麦-黑麦杂种细胞的研究

在液体培养基上用0.05%的秋水仙素处理小麦-黑麦杂种幼穗愈伤组织,含秋水仙素的培养基采用两种方法灭菌：（1）秋水仙素与培养基成分混合在一起用灭菌锅灭菌。处理愈伤后愈伤组织无伤害迹象,推测可能是灭菌过程中秋水仙素浓度降低所致;再生植株的育性得到有效的恢复,48.1%的穗子结实,5.2%的穗子结实率达到34.8%;（2）秋水仙素经超滤灭菌后,在常温下与灭过菌的培养基成分混和,处理愈伤后愈伤组织伤害严重,几乎不能分化苗。     

Temperature-mediated seasonal variation in phosphoglucomutase allozyme frequency in the yellow dung fly, Scathophaga stercoraria

The allozyme genetic variability of various species is correlated with a variety of morphological, physiological and fitness-related traits. In particular, temperature can affect the fitness of insects through its influence on enzyme function. We examined the seasonal (12 days over 1 year) and daily (nine samples over each day) allozyme variation at the phosphoglucomutase (PGM) locus in one population of yellow dung flies (Scathophaga stercoraria; Diptera: Scathophagidae). PGM is of central functional importance in the mobilization of glycogen reserves for flight, and has been shown to affect larval growth at different temperatures in the laboratory. Based on a sample of over 3000 flies, we found a quadratic relationship, with a minimum at approximately 12 degrees C, between the frequency of the most common allele and temperature, primarily mediated by seasonal temperature variation. This could be caused by behavioural responses over the short-term, but over the year either variable viability or sexual selection probably operates on this locus, maintaining the existing polymorphism. These results call for further work on the functional differences between PGM allozyme genotypes.