Identification and characterization of ten polymorphic microsatellite loci in the red panda Ailurus fulgens

Ten polymorphic microsatellite loci were characterized from two genomic DNA-enriched libraries of the red panda (Ailurus fulgens). The number of observed alleles among 35 samples of red pandas ranged from five to 12. Observed and expected heterozygosities were 0.286–0.971 and 0.443–0.894, and the mean polymorphic information content was 0.712. All loci followed Hardy–Weinberg expectations except Aifu-14 and Aifu-16, which may due to the presence of inbreeding or null alleles. Three pairs of loci exhibited significant linkage disequilibrium after Bonferroni correction for multiple comparisons. These microsatellites would be useful to strengthen population management, genetic diversity exploration, and demographic history speculation of this species.     

白芨中萜类化合物通过诱导血管内皮细胞凋亡抑制血管生成

本文研究了白芨中的萜类化合物对血管生成的抑制作用．及其抑制血管生成的可能机制。采用萃取和色谱法从白芨中分离和纯化了该萜类化合物。通过鸡胚绒毛囊膜（CAM）和人脐静脉内皮细胞（HUVEC）研究了白芨中萜类化合物及其粗提物对血管及血管内皮细胞的抑制作用。结果表明,含该萜类的粗提物显著抑制鸡胚绒毛尿囊膜血管生成;该萜类纯品能明显抑制HUVEC增殖,且可诱导HUVEC凋亡,包括细胞体积缩小,细胞膜起泡,细胞核裂解,染色质浓缩和边集,出现凋亡小体,DNA降解。因此．白芨萜类化合物的抗血管生成作用与诱导血管内皮细胞凋亡有关。     

由簇毛麦V染色体引起的小麦-簇毛麦染色体代换系、易位系中线粒体蛋白质组的变化(简报)

线粒体是需氧生物中的一种半自主性细胞器.在能量代谢中,它起了一个关键的作用,柠檬酸循环、电子传递和氧化磷酸化过程均在线粒体内完成.线粒体具有高度的生物化学和遗传上的独立性.含有DNA和核糖核蛋白体.负责合成生物体内2%-5%的蛋白质[1].线粒体DNA具有自身复制能力,控制着众多的遗传性状.在植物中广泛存在的细胞质雄性不育则被认为是由线粒体基因组控制的性状[2].     

Mitochondrial variants may influence the phenotypic manifestation of Leber's hereditary optic neuropathy-associated ND4 G11778A mutation

We report here the characterization of a five-generation Han Chinese family with Leber's hereditary optic neuropathy (LHON). Strik-ingly, this Chinese family displayed high penetrance and expressivity of visual loss. The average age-of-onset of vision loss was 18 years in this family. Nineteen (11 males/8 females) of 29 matrilineal relatives in this family developed visual loss with a wide range of severity,ranging from blindness to normal vision. Sequence analysis of mitochondrial genome in this pedigree revealed the presence of the ND4 G11778A mutation and 44 other variants belonging to Asian haplogroup M7b. The G11778A mutation is present at homoplasmy in matri-lineal relatives of this Chinese family. Of other variants, the CO1 G6480A, ND5 T12811C and Cytb A15395G located at highly conserved residues of corresponding polypeptides. In fact, these variants were implicated to be involved in other clinical abnormalities. Here, these variants may act in synergy with the primary LHON-associated Gl1778A mutation. Thus, the mitochondrial dysfunction caused by the primary ND4 G11778A mutation may be worsened by these mitochondrial variants. The results imply that the G6480A, T12811C and A15395G variants might have a potential modifier role in increasing the penetrance and expressivity of the primary LHON-associated G11778A mutation in this Chinese family.     

Identification of microsatellites in cattle unigenes

To identify EST-SSR molecular markers, 41,986 cattle UniGene sequences from NCBI were mined for analyzing SSRs. A total of 1,831 SSRs were identified from 1,666 ESTs, which represented an average density of 19.88 kb per SSR. The frequency of EST-SSRs was 4.0%. The dinucleotide repeat motif was the most abundant SSR, accounting for 54%, followed by 22%, 13%, 7% and 4%, respec-tively, for tri-, hexa-, penta- and tetra-nucleotide repeats. Depending upon the length of the repeat unit, the length of microsatellites varied from 14 to 86 bp. Among the di- and tri-nucleotide repeats, AC/TG (57%) and AGC (12%) were the most abundant type. Annotation of EST-SSRs was also carried out. Three hundred primer pairs were randomly designed using Prime Premier 5.0 program and Oligo 5.0 for further experimental validation.     

Identification and functional characterization of an aggregation domain in long myosin light chain kinase

The functions of long smooth muscle myosin light chain kinase (L-MLCK), a molecule with multiple domains, are poorly understood. To examine the existence of further potentially functional domains in this molecule, we analyzed its amino acid sequence with a tango program and found a putative aggregation domain located at the 4Ig domain of the N-terminal extension. To verify its aggregation capability in vitro, expressible truncated L-MLCK variants driven by a cytomegalovirus promoter were transfected into cells. As anticipated, only the overexpression of the 4Ig fragment led to particle formation in Colon26 cells. These particles contained 4Ig polymers and actin. Analysis with detergents demonstrated that the particles shared features in common with aggregates. Thus, we conclude that the 4Ig domain has a potent aggregation ability. To further examine this aggregation domain in vivo, eight transgenic mouse lines expressing the 4Ig domain (4Ig lines) were generated. The results showed that the transgenic mice had typical aggregation in the thigh and diaphragm muscles. Histological examination showed that 7.70 +/- 1.86% of extensor digitorum longus myofibrils displayed aggregates with a 36.44% reduction in myofibril diameter, whereas 65.13 +/- 3.42% of diaphragm myofibrils displayed aggregates and the myofibril diameter was reduced by 43.08%. Electron microscopy examination suggested that the aggregates were deposited at the mitochondria, resulting in structural impairment. As a consequence, the oxygen consumption of mitochondria in the affected muscles was also reduced. Macrophenotypic analysis showed the presence of muscular degeneration characterized by a reduction in force development, faster fatigue, decreased myofibril diameters, and structural alterations. In summary, our study revealed the existence of a novel aggregation domain in L-MLCK and provided a direct link between L-MLCK and aggregation. The possible significance and mechanism underlying the aggregation-based pathological processes mediated by L-MLCK are also discussed.     

Development of a biomimetic nanoporous membrane for the selective transport of charged proteins

We report the use of a micrometer-thick platinum-coated nanoporous membrane for the separation of differently charged proteins. A high field strength of about 25 kV m(-1) was applied, using very low transmembrane potentials of +/-1.5 V between the platinum-coated membranes. The system mimics the cell membrane function of facilitated transport for specific solutes. The selectivity for Lys:BSA:Mb in a mixed protein solution could be tuned readily between the flux ratios of 2:2:1 and 96:1:12 respectively, by simple variation of the transmembrane potentials from +1.5 V to -1.5 V. The experimental fluxes agreed closely with calculated fluxes derived from a simple electrophoresis-potential shielding model at favourable transmembrane potentials.     

Adaptive evolution and functional redesign of core metabolic proteins in snakes

Background

Adaptive evolutionary episodes in core metabolic proteins are uncommon, and are even more rarely linked to major macroevolutionary shifts.

Methodology/Principal Findings

We conducted extensive molecular evolutionary analyses on snake mitochondrial proteins and discovered multiple lines of evidence suggesting that the proteins at the core of aerobic metabolism in snakes have undergone remarkably large episodic bursts of adaptive change. We show that snake mitochondrial proteins experienced unprecedented levels of positive selection, coevolution, convergence, and reversion at functionally critical residues. We examined Cytochrome C oxidase subunit I (COI) in detail, and show that it experienced extensive modification of normally conserved residues involved in proton transport and delivery of electrons and oxygen. Thus, adaptive changes likely altered the flow of protons and other aspects of function in CO, thereby influencing fundamental characteristics of aerobic metabolism. We refer to these processes as “evolutionary redesign” because of the magnitude of the episodic bursts and the degree to which they affected core functional residues.

Conclusions/Significance

The evolutionary redesign of snake COI coincided with adaptive bursts in other mitochondrial proteins and substantial changes in mitochondrial genome structure. It also generally coincided with or preceded major shifts in ecological niche and the evolution of extensive physiological adaptations related to lung reduction, large prey consumption, and venom evolution. The parallel timing of these major evolutionary events suggests that evolutionary redesign of metabolic and mitochondrial function may be related to, or underlie, the extreme changes in physiological and metabolic efficiency, flexibility, and innovation observed in snake evolution.     

Influences of addition of different krilium in saline-sodic soil on the seed germination and growth of cabbage

China is one of the largest countries with huge amount of saline-sodic soil. How to ameliorate these lands is a hotspot in China. Through measurement of soil salinity, pH value and seed germination and growth status of cabbage seedlings, 17 kinds of krilium were added to experimented soil to evaluate their effects on amelioration of heavy saline-sodic soil. Firstly, among these 17 kinds of krilium, 11 (HPMA, gypsum, HEDP, T225, PAPEMP, MA-AA, ATMP, AA/AMPS, PAA, charcoal and BHMTPMPA) were effective agents and could effectively induce seed germination without any germination phenomena in the control saline-sodic soil. HPMA was the best one in ameliorating saline-sodic soil, which has been manifested by various indices of seed germination. Secondly, addition of gypsum together with other organic agents could strongly increase the ameliorative effectiveness if compared with relatively weak agents, while decrease seed germination if compared with the stronger agent of the 2 mixed agents, showing that the synergetic effect between gypsum and other kinds of tested krilium was not evident. Thirdly, optimum dosages for separate addition of HPMA and gypsum were 42.8 L m^?3 and 25 kg m^?3, while mixed-addition of these 2 agents at the same dosages did not cause plus effect in soil improvement. Finally, field application of HPMA could enhance the growth of cabbage seedlings at the first month, but began to wilt thereafter. Thus, instead of one-time addition, several-time addition of HPMA at the suitable dosage in field practice could strengthen the effectiveness of soil amelioration.