鲢、鳙在天然条件下的摄食强度(Ⅱ)武汉东湖鲢、鳙周年摄食强度的研究

武汉东湖的鲢(Hypophthalmichthy molitrix)鳙(Aristichthys nobilis)在天然条件下摄食强度具季节性变化。摄食强度高峰处于夏季,低谷处于冬季。在实验条件下,按周年采样期间水温变化范围,测定鱼的肠管排空率。食物通过鱼肠管时间(Y_p—h)与水温(X_t—℃)的关系为: 鲢Y_p=270.63 X_t~(0.6408) 鳙Y_p=280.46 X_t~(0.6642) 根据修正后Bajkov公式(D=C (24.A)/n),估算鱼的日粮。鱼日粮(Y_D)与水温(X_t)关系为: 鲢Y_D=0.2683e~(0.1503X_t) 鳙Y_D=0.0075X_t~(2.2715) 计算鱼在天然条件下周年月粮及年粮。鲢、鳙对天然饵料年消耗量分别为18.924公斤及17.39公斤,饵料系数分别为18.02及13.38。     

Overexpression of the chitinase gene CmCH1 from Coniothyrium minitans renders enhanced resistance to Sclerotinia sclerotiorum in soybean

Transgenic Research - Pathogenic fungi represent one of the major biotic stresses for soybean production across the world. Sclerotinia sclerotiorum, the causal agent of Sclerotinia stem rot, is a...     

PKC delta phosphorylates p52ShcA at Ser29 to regulate ERK activation in response to H2O2

Both PKC delta and ShcA have been implicated in cell response to oxidative stress [Y. Hu, X. Wang, L. Zeng, D.Y. Cai, K. Sabapathy, S.P. Goff, E.J. Firpo, B. Li, Mol Biol Cell., 16 (2005) 3705-3718, B. Li, X. Wang, N. Rasheed, Y. Hu, S. Boast, T. Ishii, K. Nakayama, K.I. Nakayama, S.P., Goff, Genes Dev, 18 (2004) 1824-1837, E. Migliaccio, M. Giorgio, S. Mele, G. Pelicci, P. Reboldi, P.P. Pandolfi, L. Lanfrancone, P.G. Pelicci, Nature, 402 (1999) 309-313], yet their relationship in the response has not been studied. Here we report that PKC delta interacts with ShcA and this interaction is promoted by H(2)O(2). PKC delta and ShcA are also colocalized in the cytoplasm and displayed co-translocation in response to H(2)O(2). Activated PKC delta was able to phosphorylate ShcA at Ser29, as determined by mass spectrometry. These results suggest that ShcA, p66 and p52, are substrates that interact with PKC delta. This phosphorylation is critical in H(2)O(2) induced ERK activation as reconstitution with ShcA Ser29A failed to rescue ERK activation of ShcA-/- MEFs, while ShcA could. In line with this conclusion, inhibition of PKC delta with inhibitors is able to diminish H(2)O(2) induced ERK activation in MEFs. These results suggest that the interaction between PKC delta and ShcA and the phosphorylation of ShcA at Ser29 play important roles in ERK activation in cell response to H(2)O(2).     

ERK phosphorylates p66shcA on Ser36 and subsequently regulates p27kip1 expression via the Akt-FOXO3a pathway: implication of p27kip1 in cell response to oxidative stress

Mice deficient for p66shcA represent an animal model to link oxidative stress and aging. p66shcA is implicated in oxidative stress response and mitogenic signaling. Phosphorylation of p66shcA on Ser36 is critical for its function in oxidative stress response. Here we report the identification of ERK as the kinase phosphorylating p66shcA on Ser36. Activation of ERKs was necessary and sufficient for Ser36 phosphorylation. p66shcA interacted with ERK and was demonstrated to be a substrate for ERK, with Ser36 being the major phosphorylation site. Furthermore, in response to H2O2, inhibition of ERK activation repressed p66shcA-dependent phosphorylation of FOXO3a and the down-regulation of its target gene p27kip1. Down-regulation of p27 might promote cell survival, as p27 played a proapoptotic role in oxidative stress response. As a feedback regulation, Ser36 phosphorylated p66shcA attenuated H2O2-induced ERK activation, whereas p52/46shcA facilitated ERK activation, which required tyrosine phosphorylation of CH1 domain. p66shcA formed a complex with p52/46ShcA, which may provide a platform for efficient signal propagation. Taken together, the data suggest there exists an interplay between ERK and ShcA proteins, which modulates the expression of p27 and cell response to oxidative stress.     

曾候乙墓穴木椁微生物的分离与鉴定

从曾侯乙墓中椁室、东椁室、西椁室和北椁室分别取样,经平板划线培养,分离,纯化共获得典型的菌株16株。将16株分别涂片镜检,生理生化分析鉴定,结果证明芽孢杆菌属11株,其中苏云金变种1株,地衣芽孢杆菌1株,巨大芽孢杆菌1株,球形芽孢杆菌5株,蜡状芽孢杆菌2株,多粘芽孢杆菌1株。其余菌株微杆菌属4株,黄色杆菌属黄杆菌1株。     

曾候乙墓穴木椁微生物降解对木材危害及防治措施研究

从曾候乙墓分离到的16株菌,其中有11株为芽孢杆菌属类,4株微杆菌属,1林为黄色杆菌属。将16株细菌分别侵染6种木材,结果证明细菌降解对6种木材均有不同的韧性下降,个别木材出现腐烂病灶。2号菌降解后对泡桐、枣树、马尾松、香樟、刺槐和桑树分别下降8％,12％,10％,5％,10％和13％。3,5,6,7,8,9和16号菌对上述6种木材也有不同程度影响。而4,11,12,13,14和15号菌对6种木材的韧性下降影响不明显。但其渗透性大大提高了,因此也会影响木材的使用年限。采用杀菌、杀虫的石油气,乙醇等有机溶济,防治微生物降解产物对木材的浸蚀,均有较好的防菌、防认腐效果。     

Polysaccharides from Dicliptera chinensis ameliorate liver disturbance by regulating TLR-4/NF-κB and AMPK/Nrf2 signalling pathways

The purpose of this study was to alleviate liver disturbance by applying polysaccharides from Dicliptera chinensis (DCP) to act on the adenosine monophosphate–activated protein kinase/ nuclear factor erythroid 2-related factor 2 (AMPK/ Nrf2) oxidative stress pathway and the Toll-like receptor 4 (TLR-4)/ nuclear factor kappa-B (NF-κB) inflammatory pathway and to establish an in vivo liver disturbance model using male C57BL/6J and TLR-4 knockout (^−/−) mice. For this, we evaluated the expression levels of SREBP-1 and Nrf2 after silencing the expression of AMPK using siRNA technology. Our results show that with regard to the TLR-4/ NF-κB inflammatory pathway, DCP inhibits TLR-4, up-regulates the expression of peroxisome proliferator-activated receptor-γ (PPAR-γ), reduces the expression of phospho(p)-NF-κB and leads to the reduction of downstream inflammatory factors, such as tumour necrosis factor-α (TNF-α), interleukin (IL)-6 and IL-1β, thereby inhibiting the inflammatory response. Regarding the AMPK/ Nrf2 oxidative stress pathway, DCP up-regulates the expression of p-AMPK and Nrf2, in addition to regulating glucose and lipid metabolism, oxidative stress and ameliorating liver disturbance symptoms. In summary, our study shows that DCP alleviates liver disturbances by inhibiting mechanisms used during liver inflammation and oxidative stress depression, which provides a new strategy for the clinical treatment of liver disturbance.     

海南国家公园霸王岭片区无尾两栖类鸣声多样性:基于自动录音技术

海南热带雨林国家公园霸王岭片区属于我国生物多样性热点地区,其自然环境非常适合两栖类生存,但该区域的无尾两栖类多样性情况尚不清楚。本研究利用新兴的生物声学方法,调查该地区无尾两栖动物的多样性,并了解蛙类鸣叫与环境的关系。我们在国家公园霸王岭片区选择5个生境不同的区域,每个区域设置一条样线,每条样线上布设3台录音设备,于2021年6月、8-9月和12月以及2022年1-3月分别收集至少半个月的声音数据。本次调查共记录到蛙类17种,隶属6科11属。四季的物种组成存在差异,其中冬季(12月)出现的物种最少。不同区域的物种组成也存在差异,其中飞列地区发现的物种最多。记录到的17种蛙中,有12种仅在夜晚鸣叫,有3种主要在夜晚鸣叫,偶尔也在白天鸣叫,有2种全天都活跃鸣叫。不同生境蛙类对降雨的响应也存在差异。永久水体中的小湍蛙(Amolops torrentis)和沼水蛙(Hylarana guentheri),以及栖息环境多样的饰纹姬蛙(Microhyla fissipes),鸣叫活性不受降雨影响,但浅水溪流中的脆皮大头蛙(Limnonectes fragilis)和地面上的海南拟髭蟾(Leptob...