基于转录组的肝豆状核变性调控网络的构建和分析

本研究旨在利用生物信息学方法构建经铜诱导的ATP7B基因敲除HepG2细胞系的转录调控网络。探讨关键转录因子在肝豆状核变性发生、发展中的潜在作用机制。收集公共基因表达数据库(gene expression omnibus, GEO)中包含野生型、ATP7B基因敲除型、铜诱导的野生型和铜诱导的ATP7B基因敲除型HepG2细胞系数据。筛选由铜诱导产生的差异表达基因(differentially expressed genes,DEGs)后进行基因本体论(gene ontology,GO)、京都基因和基因组百科全书(Kyoto encyclopedia of genes and genomes, KEGG)富集分析。基于蛋白相互作用网络,识别疾病关键基因和功能模块,并对关键功能模块中的基因进行富集分析。最后,构建转录调控网络,筛选核心转录因子。共筛选出1 034个差异表达基因,其中上调525个,下调509个。上、下调关键功能模块分别包括了3785个和3931个基因。关键功能模块中的基因主要定位于细胞-基质连接、染色体、剪接复合体、核糖体等区域,共同参与了mRNA加工、组蛋白修饰、RNA剪切...     

SRAP、ISSR技术的优化及在甘蓝类植物种子鉴别中的应用

将SRAP与ISSR 2种分子标记技术应用于8种甘蓝类植物（Brassica oleracea L.）的种子鉴别中。先以甘蓝（Brassica oleracea var. capitata）基因组DNA为模板,通过对SRAP、ISSR反应体系中各影响因素的逐一筛选,优化了甘蓝类植物SRAP、ISSR反应体系。进而采用30个SRAP引物组合和15个ISSR引物对白甘蓝、皱叶甘蓝、红甘蓝、羽衣甘蓝、花椰菜、青花菜、抱子甘蓝、球茎甘蓝的基因组DNA进行了PCR扩增,结果表明：M3E5与M4E5两个SRAP引物组合可以在8种甘蓝类植物之间显示较高的多态性;844和888两个ISSR引物也可在8种甘蓝类植物之间产生很好的多态,特别是844引物单独应用即可区分所有材料。     

Fifteen polymorphic simple sequence repeat markers from expressed sequence tags of Liriodendron tulipifera

We developed and evaluated simple sequence repeat (SSR) markers derived from expressed sequence tags (ESTs) of Liriodendron tulipifera. Characteristics of 15 EST‐SSR loci were investigated using 33 L. tulipifera individuals. The number of alleles per locus ranged from two to five. The expected and observed heterozygosities ranged from 0.216 to 0.751 and from 0.182 to 0.97, respectively. These loci were further tested for their cross‐species transferability to Liriodendron Chinense. Because of their high level of polymorphism and transferability, our 15 single‐locus EST‐SSR markers will be valuable tools for research on mating system, population genetics and systemic evolution of Liriodendron.     

中国森林生态资产价值评估

森林资源是支撑人类社会发展的重要生态资产,探索森林生态资产价值的评估方法,对合理利用和有效保护森林资源具有重要意义。运用净现值法计算了中国森林生态资产总价值为698.5万亿元,其中直接价值为7.5万亿元,包括林木价值4.5万亿元和林下产品价值3.0万亿元;间接价值为691万亿元,其中,气候调节价值量最高,占间接价值的48%;水源涵养价值量次之,占间接价值的27%。从森林生态资产总价值的分布来看,广西省、广东省和云南省位于全国前列,分别占森林生态资产总价值的10%、9%和9%。单位面积森林生态资产价值表现为海南省、浙江省和广东省较高,分别为954万元/hm2,915万元/hm2和888万元/hm2。森林生态资产价值研究为我国编制自然资源资产负债表提供理论依据,因此全面的估算中国森林生态资产价值很有意义。     

鸭绿江香鱼耳石日轮与生长的研究

１９９２年对鸭绿江香鱼耳石日轮与生长进行了研究。人工受精卵胚胎发育后期和前仔鱼期连续剖察表明，受精后约９６小时胚体听囊内出现一对矢耳石，孵出后第２天耳石上出现第一个日轮，之后每天形成一轮。在光镜和扫描电镜下测定了幼、成鱼矢耳石的形态、直径、日轮数及其间距变化。耳石短径（ｖ， μｍ）与鱼体长（ｘ， ｍｍ）呈线性关系， ７５尾幼、成鱼的关系式为ｙ＝３．２８ｘ＋２４８．３０。以耳石日轮数推算其产卵孵化期与实地调查结果一致。耳石日轮数（Ｄ）可用孵化后日数（Ｎ）减１表示。日轮间距有规律性变化，与鱼体生长发育和生态条件密切有关。依据日龄和相关体长体重资料进行了香鱼生长特性研究，用生长方程描绘的生长速度曲线和生长拐点（位于２８３日龄）等均较客观地反映了其生长特点。     

G蛋白偶联受体与G蛋白相互作用的最新研究进展

传统观念认为,在激动剂作用下,G蛋白偶联受体(GPCRs)能够激活G蛋白的α亚基,从而使Gα亚基与Gβγ亚基分离,被激活的Gα亚基通过信号转导进一步参与细胞的生理过程。但是,最新研究发现GPCRs和G蛋白存在多种偶联关系,GPCRs不仅能够激活Gα亚基,还可以与Gβγ亚基相互靠近,甚至会使G蛋白亚基构象发生重排而不分离,这对于疾病发病机制的研究及新的药物靶点的发现具有重要意义。就GPCRs与G蛋白之间的相互作用以及最新研究技术作一简要综述。     

Survival of caddis larvae in relation to their case material in a group of temporary and permanent pools

1. The occurrence of larvae of Limnephilus coenosus and L. vittatus (Trichoptera) was recorded in 103 rock pools both before and after the dry periods in spring–summer (April–May and July–early August), when a great number of the pools dried out. In early spring, 84% of the pools sampled contained larvae of at least one of the species. Limnephilus coenosus larvae were present in a higher proportion of pools that later dried out than in the permanent ones, while L. vittatus larvae were predominantly found in permanent pools. Larvae of both species were found together in 31% of the inhabited pools.
2. Laboratory experiments, designed to elucidate differential survival under drought conditions, demonstrated that the organic cases of L. coenosus larvae held water more efficiently than did the mineral L. vittatus cases. Full-grown (fifth instar) L. coenosus larvae also survived dry conditions better than did L. vittatus larvae. The higher survival of L. coenosus was due to a combination of drought-resistant case material and a higher survival ability of the larvae themselves.
3. Limnephilus vittatus larvae were restricted by their low capability to withstand desiccation, although case material and food were available for L. vittatus larvae in all pools. Absence of case material and high-quality food in many pools, however, restricted the presence of L. coenosus larvae, but this species did not suffer from heavy mortality because of desiccation and all pool populations of L. coenosus survived until pupation.
4. The differences in species composition in these temporary and permanent pools can be explained by the differential site selection by ovipositing females, as well as by larval survival. The intrinsically greater survival of L. coenosus larvae during drought, together with the water-retaining properties of the cases, allowed this species to exploit stressful and risky habitats, such as temporary pools.