植物种群表观竞争机制及其研究进展

植物表观竞争既影响群落结构和组成,也与生态系统功能密切相关。目前,国内尚缺乏对植物表观竞争的实验研究和机制探索。对植物表观竞争概念和研究进展进行了系统梳理和阶段性总结,分析了草食动物为媒介的表观竞争主要通过食物和生境介导植物竞争过程,以及ELP-采食者关系对表观竞争的影响;植物参与的表观竞争通常与资源竞争共同作用;AM真菌为媒介的表观竞争不仅受到宿主植物菌根依赖性的影响,还与AM真菌对资源的需求和环境资源供给状况有密切关系。未来研究既要注重实验设计的合理性,也要考虑测定方法和评价参数的有效性;重视植物群落和生态系统水平上表观竞争的功能研究。这不仅能够为植物群落结构和物种共存提供机制性解释,而且能够丰富经典的植物竞争理论和多营养级相互作用的食物网理论。     

Molecular Determinants of Calpain-dependent Cleavage of Junctophilin-2 Protein in Cardiomyocytes

Junctophilin-2 (JP2), a membrane-binding protein that provides a structural bridge between the plasmalemma and sarcoplasmic reticulum, is essential for precise Ca²⁺-induced Ca²⁺ release during excitation-contraction coupling in cardiomyocytes. In animal and human failing hearts, expression of JP2 is decreased markedly, but the molecular mechanisms underlying JP2 down-regulation remain incompletely defined. In mouse hearts, ischemia/reperfusion injury resulted in acute JP2 down-regulation, which was attenuated by pretreatment with the calpain inhibitor MDL-28170 or by transgenic overexpression of calpastatin, an endogenous calpain inhibitor. Using a combination of computational analysis to predict calpain cleavage sites and in vitro calpain proteolysis reactions, we identified four putative calpain cleavage sites within JP2 with three N-terminal and one C-terminal cleavage sites. Mutagenesis defined the C-terminal region of JP2 as the predominant calpain cleavage site. Exogenous expression of putative JP2 cleavage fragments was not sufficient to rescue Ca²⁺ handling in JP2-deficient cardiomyocytes, indicating that cleaved JP2 is non-functional for normal Ca²⁺-induced Ca²⁺ release. These data provide new molecular insights into the posttranslational regulatory mechanisms of JP2 in cardiac diseases.     

Evolution of Multilevel Social Systems in Nonhuman Primates and Humans

Multilevel (or modular) societies are a distinct type of primate social system whose key features are single-male–multifemale, core units nested within larger social bands. They are not equivalent to fission–fusion societies, with the latter referring to routine variability in associations, either on an individual or subunit level. The purpose of this review is to characterize and operationalize multilevel societies and to outline their putative evolutionary origins. Multilevel societies are prevalent in three primate clades: papionins, Asian colobines, and hominins. For each clade, we portray the most parsimonious phylogenetic pathway leading to a modular system and then review and discuss likely socioecological conditions promoting the establishment and maintenance of these societies. The multilevel system in colobines (most notably Rhinopithecus and Nasalis) has likely evolved as single-male harem systems coalesced, whereas the multilevel system of papionins (Papio hamadryas, Theropithecus gelada) and hominins most likely arose as multimale–multifemale groups split into smaller units. We hypothesize that, although ecological conditions acted as preconditions for the origin of multilevel systems in all three clades, a potentially important catalyst was intraspecific social threat, predominantly bachelor threat in colobines and female coercion/infanticide in papionins and humans. We emphasize that female transfers within bands or genetic relationships among leader males help to maintain modular societies by facilitating interunit tolerance. We still lack a good or even basic understanding of many facets of multilevel sociality. Key remaining questions are how the genetic structure of a multilevel society matches the observed social effort of its members, to what degree cooperation of males of different units is manifest and contributes to band cohesion, and how group coordination, communication, and decision making are achieved. Affiliative and cooperative interunit relations are a hallmark of human societies, and studying the precursors of intergroup pacification in other multilevel primates may provide insights into the evolution of human uniqueness.     

The primate extinction crisis in China: immediate challenges and a way forward

China is facing an unprecedented set of challenges in balancing the effects of economic development and global climate change with environmental protection and maintaining biodiversity. Although positive steps have been undertaken to remedy this situation, currently 80% of China’s 25 extant primate species are threatened, 15–18 species have population sizes of less than 3000 individuals, and two species of gibbons and one species of langur have been extirpated over the past few decades. Today, virtually all species of primates in China inhabit fragmented landscapes and are distributed in small isolated subpopulations with limited opportunities to exchange individuals or genetic information. Here we present a historical framework examining how human-induced environmental changes, particularly since the second half of the 20th century, accelerated primate population decline in China. In addition, we modeled the expected spatial conflict between agricultural expansion and primate distributions over the next 25–75 years and assessed the current overlap between protected areas and primate distributions. Depending on the assumptions of the spatial conflict model, primate distributions are expected to decline by an additional 51–87% by the year 2100. Thus, unless large-scale conservation policies are implemented immediately the current trend of primate population decline, local extirpation, and species extinctions will accelerate. To mitigate against such extinction scenarios, we advocate the creation of a Chinese national agency and repository of environmental information focused on public awareness and education, the implementation of targeted programs of habitat restoration designed to return impacted forests to a more natural state especially within and at the boundaries of nature reserves, the establishment of additional protect areas, and the construction of a latticework of corridors connecting isolated primate subpopulations. This comprehensive approach offers the most effective way to protect China’s animal and plant biodiversity, including its endangered primate populations.     

Dietary diversity of an ecological and macronutritional generalist primate in a harsh high‐latitude habitat,the Taihangshan macaque (Macaca mulatta tcheliensis)

Recent advances in niche theory have stressed the importance of understanding dietary generalism at multiple levels, including the range of habitat and foods exploited by a species, foods exploited within populations, and patterns of nutrient intake. Here we apply this framework to examine the dietary strategy of the Macaca mulatta, a primate species that is second only to humans in their breadth of geographical distribution, and occupy diverse ecological habitats from cold temperate to tropical latitudes. A recent study showed that the Taihangshan subspecies ( M. mulatta tcheliensis) in China, which is found at the northern latitudinal limit of the species range, respond to ecologically constrained interannual variation in the macronutrient ratios of the spring diet in a way that theory predicts should be associated with ecological generalism. Here we further extend this study, examining the relationships between seasonal variation in food availability and the patterns of food selection across a full year. We found that, despite the ecological and macronutritional generalism of the species, Taihangshan macaques subsist on a relatively small range of foods (57 different foods, spread across 8 categories comprising seeds, fruits, buds, flowers, leaves, herbs, young bark, and twigs), but face considerable seasonal variation in the combinations available. In spring and summer, when seeds were scarce, leaves accounted for 60.3 ± 13.8% of their diet (dry matter [DM] %), and herbs contributed 31.7 ± 22.2%. However, in autumn and winter, when seeds were abundant, they contributed 68.5 ± 22.7% of the diet while herbs accounted for 18.9 ± 12.9% on a DM. Although young bark and twigs were available in all seasons, the macaques only fed on them in winter. We present comparative data from the literature on the diets of M. mulatta and other Macaca species, to interpret this pattern of resource use within the framework of multilevel niche theory.     

烈香杜鹃的离体培养和高效植株再生

以烈香杜鹃嫩茎为外植体,应用均匀设计法筛选其最适合的嫩茎基部直接再生芽苗和生根培养基。结果表明,最适合烈香杜鹃嫩茎基部直接再生芽苗的诱导培养基为DR＋2．30mg·L-1 TDZ＋0．05mg·L-1 IAA＋1．80mg·L-1 KT,诱导率为99．6％;生根培养基为1／2DR＋0．07mg·L-1 IAA＋0．02mg·L-1NAA,生根率达99．7％以上。以再生植株茎节为材料进行快速繁殖,在35d的培养周期内,每段增殖倍数平均达5以上。     

CRBGP通过抑制FAK-AKT通路和白介素-6的分泌抑制胶质瘤U251细胞的活性

目的 电压门控钠通道(voltage-gated sodium channels,VGSCs)表达于胶质瘤U251细胞,并影响U251细胞的增殖、侵袭和凋亡.富含半胱氨酸的颊腺蛋白(cysteine-rich buccal gland protein,CRBGP)是一种从日本七鳃鳗颊腺中分离出来的VGSCs阻断剂.本文...     

云南白马雪山自然保护区猕猴和滇金丝猴的生态位分离(英文)

原则上,食叶的滇金丝猴(Rhinopithecus bieti)和杂食的猕猴(Macaca mulatta)是可以同地共栖的,但这两种灵长类究竟是如何同地共存却一直是一个鲜见涉足的问题。该文初步通过分析它们的食性和生境需求来阐明两者共存的可能性。在猕猴取食约22种植物中,有16种也是滇金丝猴的取食对象。两种灵长类都显示出喜食果实。人们尚未发现滇金丝猴涉足人类作物等相关资源,但发现猕猴经常侵食庄稼。这与其生活海拔不同有关:滇金丝猴一般生活在平均海拔为3218m的山林中,而猕猴活动在平均海拔为2995m的林地。猕猴也会涉足牧场,而滇金丝猴回避这种场地。对于这两个种,混合的落叶阔叶/针叶林是最频繁使用的森林类型;滇金丝猴很少进入常绿阔叶林(青冈属群落,利用率仅3%),而猕猴相对进入这类林型的机会远比滇金丝猴高(36%)。两个物种的群体间常相互远离(2.4km)。当其相遇时,常是猕猴主动回避。上述结果提示滇金丝猴和猕猴是通过大生境分化利用和空间避让来共存的。尽管不同的生境利用策略一定程度上会反映种间竞争的存在,但这种不同更可能反映着它们不同的生理/生态需求。