生物钟基因在绒山羊皮肤中表达模式的比较     

贾丽丽  金凤  付绍印  郑竹清  杜琛  季小阳  王志新  李金泉  刘少卿  张文广 《中国畜牧兽医》2015,42(2):251-257

文章旨在研究绒山羊皮肤生物钟基因clock、tim、per1和cry1的表达模式,进而分析其在绒山羊皮肤组织中的作用及相互关系。生物钟基因形成一个转录-翻译反馈环,通过钟基因在绒山羊皮肤生长周期进行高表达,激活per1和cry1基因的转录-转化过程,从而在mRNA和蛋白水平的调控下进行有节律的表达。结果表明,这些生物钟基因在绒山羊皮肤中的表达量依次为:clocktimper1cry1;皮肤次级毛囊兴盛期,高振幅clock、per1、tim、cry1的节律表达分别出现在一天中的04∶00、08∶00、08∶00、16∶00;皮肤次级毛囊休止期,这些基因的高振幅节律表达分别出现在一天中的08∶00、04∶00、04∶00、16∶00。另外,cry1、per1基因的表达在生物钟基因正反馈循环中被激活,tim基因的表达在生物钟基因的负反馈循环中被激活。因此,clock、tim、per1和cry1调控下运行的钟基因反馈环是绒毛生长呈周期性现象的基础。  相似文献   

Saliva chromogranin A in growing pigs: A study of circadian patterns during daytime and stability under different storage conditions     

Damián Escribano  Ana M. Gutiérrez  María Fuentes-Rubio  José J. Cerón 《Veterinary journal (London, England : 1997)》2014,199(3):355-359

Salivary chromogranin A (CgA) is considered to be a biomarker of activation of the sympatho-adrenomedullary system, and has recently been proposed as a useful indicator of the acute stress response in pigs. The aim of the present study was to determinate whether salivary CgA concentrations in healthy growing pigs exhibits any circadian pattern during the daytime, and to evaluate its stability under different storage conditions. A total of 80 pigs (40 in spring and another 40 in autumn) of two different ages and genders were used. To establish the circadian pattern, saliva samples were collected at 07.00, 11.00, 15.00 and 19.00 h on two consecutive days. Pooled samples were used for the stability study and were measured on the day of sampling and periodically for up to 360 days later. Samples were stored at 4 °C, ?20 °C or ?80 °C and the effect of repeated freezing and thawing was also evaluated.No circadian pattern was detected for salivary CgA in either season and there were no significant effects of gender or age. However, mean salivary CgA concentrations were significantly higher (P < 0.0001) in the pigs sampled in autumn, compared to those sampled in the spring. Short term storage at 4 °C is recommended for up to 2 days, whereas frozen samples can be stored for 1 year at ?20 °C or ?80 °C, without substantial reduction in CgA values. In addition, samples can be frozen and thawed up to seven times without significant loss of the biomarker.  相似文献   

混合时钟同步技术在船舶电力系统同步相量测量中的应用研究     

王黎明  闫晓玲  卜乐平 《湖南农业大学学报(自然科学版)》2014,(2):52-56

针对船舶电力系统相对于陆地广域电力系统的不同特性,分析传统时钟同步方法对于船舶同步向量测量单元（SPMU）的局限性,采用一种基于IEEE1588协议的卫星时钟同步与局域网时钟同步相结合的混合时钟同步技术实现SPMU的时钟同步,通过实验对同步偏差性能进行测试,结果表明时钟同步偏差维持在±500ns以内,可以满足电力系统对电力参数测量的同步精度要求。  相似文献   

枣粘虫性行为时辰节律的研究   总被引：2，自引：0，他引：2  

李连昌  任自立 《林业科学》1991,27(2):145-148

本文利用腺体提取、瓶内收集、触角电位和田间试验等方法对枣粘虫产生和释放性信息素时辰节律进行了研究。其中瓶内收集性信息素的方法,在研究昆虫释放性信息素时辰节律方面报道很少,更重要的是,此法在我们的实验中取得了比较满意的效果。研究结果表明:(1)羽化后1—6天的提取物产生的触角电位无明显差异,说明性信息素在此期间的产生与日龄无关(2)腺体中性信息素的含量高峰在凌晨4点,而从体内往体外释放的高峰在早晨7点。(3)利用处女雌蛾不同时辰的诱蛾量的田间试验也进一步证明了枣粘虫产生和释放性信息素与交配行为在时辰节律上的同步性。  相似文献   

毛囊发育与毛发生产研究进展   总被引：2，自引：0，他引：2  

王宁  荣恩光  闫晓红 《东北农业大学学报》2012,(9):6-12,145

毛囊是皮肤的衍生物,其结构复杂,由多层独特的细胞构成.毛囊是哺乳动物惟一终生呈周期性生长的器官.毛发是毛囊生长发育的产物,由死亡的终末分化角质细胞组成.动物毛发是重要的畜产品,是纺织工业的重要原料.近年来,毛囊发育和毛发生产的分子遗传学研究进展迅速,许多调控毛囊形态发生和毛发周期的信号通路以及基因相继被发现和鉴定.这些调控通路及基因的发现和鉴定提高对毛囊发育和毛发生产的了解和认识,为采用分子辅助育种和转基因育种技术培育优质细毛羊奠定了理论基础.文章综述了毛囊形态发生、毛发周期以及毛干特性的调控等最新研究进展,并讨论了未来羊毛囊发育研究方向.  相似文献   

Circadian protein Cry2 is a prognostic factor of colorectal cancer and a predictor of chemotherapy     

ZHOU Jun-yi  FANG Le-kun  DENG Yan-hong  LIU Huan-liang  WANG Lei  WANG Jian-ping  HUANG Mei-jin 《园艺学报》2012,28(8):1373-1377

AIM:To assess the association between the expression of Cry2 and the prognosis of colorectal cancer for determining the role of Cry2 in predicting the outcome of chemotherapy. METHODS:Sixteen primary colorectal cancer patients who consecutively underwent neoadjuvant chemotherapy with 5-fluorouracil were enrolled in the present study. The tumor specimens were obtained by colonscopy prior to treatment. The tumor response was evaluated by the response evaluation criteria in solid tumors(RECIST). Accordingly, the patients were divided into 2 groups:complete response(CR)/partial response(PR) and stable disease(SD)/progress disease(PD). Two-tail ² test was applied to analyze the data. In parallel, we assessed 307 patients, who underwent tumor resection between 2001 and 2005. Survival time was calculated from the date of surgery to the date of death or the last follow-up date. Survival curves were obtained by Kaplan-Meier method. Log-rank test was applied for univariate analysis. The Cox proportional hazards regression model was used to identify the independent prognostic factors. RESULTS:The expression of Cry2 was high in CR/PR patients and was low in SD/PD patients, with significant difference(P<0.05). The average survival time of the 84 patients with high expression of Cry2 was 83.458 months, while the average survival time of 223 patients with low expression of Cry2 was 100.10 months, also with significant difference(P<0.05). The patients with low expression of Cry2 lived longer. The multivariate Cox regression analysis indicated that the expression of Cry2 was an independent prognostic factor for colorectal cancer patients(HR was 1.70, 95% CI was 1.09 to 2.66, P<0.05). Multivariate Cox regression showed that high Cry2 expression predicted a worse prognosis(HR was 2.88, 95%CI was 1.03 to 8.06, P<0.05) in colorectal cancer patients with neoadjuvant chemotherapy. CONCLUSION:Expression of Cry2 is an independent prognostic factor for colorectal cancer patients. Lower expression of Cry2 indicates good response to neoadjuvant chemotherapy.  相似文献   

杨树生物钟节律基因PtCCA1的克隆及表达模式研究          下载免费PDF全文

刘无双  杜明会  陶维康  杨贞  诸葛强 《林业科学研究》2013,26(5):649-654

生物钟节律基因CCA1在植物的光周期反应中起着重要的调控作用.利用RT-PCR方法克隆获得了一条包含1902 bp开放阅读框的杨树CCA1基因cDNA序列,其编码633个氨基酸残基,蛋白的分子量约为68.90 kDa,等电点为6.33.分析显示含有1个Myb-like DNA结合域及2个蛋白跨膜结合域.实时荧光定量PCR分析发现,PtCCA1基因主要在杨树叶组织中表达;随着光照时间的变化,该基因在杨树中的表达量呈现白昼不断降低而夜晚逐渐升高的昼夜变化趋势.研究结果为进一步探索PtCCA1基因在调控杨树光周期响应途径中的功能以及杨树光周期敏感机制提供了科学基础.  相似文献   

Monitoring the circadian rhythm of serum and salivary cortisol concentrations in the horse     

Zs. Bohák  F. Szabó  J.-F. Beckers  N. Melo de Sousa  O. Kutasi  K. Nagy  O. Szenci 《Domestic animal endocrinology》2013

Daily fluctuations of cortisol concentration in the blood or saliva have been repeatedly reported. However, several contradictions in the existing literature appear on this subject. The present study was performed to definitively establish options for testing adrenocortical function. To the best of our knowledge, this is the first study to evaluate parallel circadian rhythms in salivary and serum cortisol concentrations during a 24-h period. Twenty horses were examined under the same conditions. Blood and saliva samples were taken every 2 h for 24 h to determine the daily changes in cortisol concentrations of saliva and serum at rest and to determine the relationship between salivary and serum cortisol levels. Cosinor analysis of group mean data confirmed a significant circadian component for both serum and salivary cortisol concentrations (P < 0.001 in both cases). The serum cortisol circadian rhythm had an acrophase at 10:50 AM (95% CI, 10:00 AM–11:40 AM), a MESOR of 22.67 ng/mL, and an amplitude of 11.93 ng/mL. The salivary cortisol circadian rhythm had an acrophase at 10:00 AM (95% CI, 9:00 AM–11:00 AM), a MESOR of 0.52 ng/mL, and an amplitude of 0.12 ng/mL. We found a significant but weak association between salivary and serum cortisol concentrations; the Pearson correlation coefficient was 0.32 (P < 0.001). The use of salivary cortisol level as an indicator of hypothalamic-pituitary-adrenal axis activity may be warranted. However, the salivary cortisol levels are more likely to be correlated with free plasma cortisol than with the total plasma cortisol concentration.  相似文献   

鳞翅目昆虫生物钟的研究进展与展望     

全林发  姚琼  董易之  徐淑  池艳艳  陈炳旭 《农学学报》2023,13(9):38-45

经过长期的自然演化,昆虫生命活动和行为中有着明显的昼夜和季节的节律性周期变化——生物钟(circadian clock)。鳞翅目昆虫是当前物种最丰富的昆虫群体,包括蝴蝶和飞蛾约16万种,其中近70%的重要农林害虫属于鳞翅目。而鳞翅目昆虫生物钟的研究进展对于深入剖析鳞翅目昆虫丰富多变的生理行为调控机制,有效开展鳞翅目经济昆虫的生产及农林害虫防治具有重要意义。总结了昼夜节律生物钟对鳞翅目昆虫孵化与取食、生长与变态、生殖与滞育、求偶与迁飞等生理行为的影响,重点概述了鳞翅目昆虫生物钟分子调控机制、生物钟与内分泌激素协同调控机制等重要研究进展,并基于生物钟原理探讨了鳞翅目昆虫与植物协同进化关系及重要生态意义,展望了将生物钟理论应用于农业害虫防治和经济昆虫饲养改良的应用前景。  相似文献   

Diversity in daytime and night‐time transpiration dynamics in barley indicates adaptation to drought regimes across the Middle‐East     

Walid Sadok  Bishal G. Tamang 《Journal of Agronomy and Crop Science》2019,205(4):372-384

A challenge to breeding drought‐tolerant barley in the Middle‐East is that precipitation and evaporative demand patterns dictate opposite water use strategies (conservative vs. risk‐taking). To characterize these strategies, we examined high‐resolution, whole‐plant transpiration rate (TR) responses to increasing vapour pressure deficit (VPD) and nocturnal TR (TR_N) dynamics among 25 local barley genotypes, using a novel phenotyping system. These traits were specifically selected because they exist under modalities enabling the expression of both strategies. The genotypes were selected from locations spread across a large aridity gradient represented by temperature and precipitation data spanning 30 years. Here, we uncovered a substantial diversity in TR responses to VPD where slopes of the linear responses correlated negatively with local maximal temperatures, pointing to opposite drought tolerance strategies. Low canopy conductance (low slopes) was associated with higher aridity, likely to enable water‐saving, while higher conductance was associated with wetter areas, likely to enable a more aggressive water use to maximize physiological activity. TR_N was highly diverse and represented up to 15% of maximal daytime TR, pointing to the possibility of increasing water‐saving by reducing TR_N. Furthermore, we detected pre‐dawn variation in TR_N that negatively correlated with local precipitation, indicating that a tighter circadian control is associated with adaptation to drought, consistently with a circadian resonance mechanism. These findings indicate that canopy conductance and TR_N are potentially beneficial to design drought‐tolerant barley germplasm adapted to different drought regimes taking place in the Middle‐East.  相似文献