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991.
COMM domain-containing proteins are a group of recently discovered proteins; their biochemical characterization remains much limited. Here we demonstrate that a cDNA encoding Branchiostoma belcheri COMMD6, designated BbCOMMD6, codes for a protein of 203 amino acids, with a COMM domain at its C-terminal region and an extended N-terminal portion. BbCOMMD6 is mainly present in the cytosol. In contrast to COMMD1, the presence of Cu(II) cannot enhance recombinant BbCOMMD6 dimer formation. Both the pull-down and reverse pull-down assays reveal that BbCOMMD6 interacts with the creatine kinase (CK), an essential enzyme involved in energy metabolism, forming a heterodimer BbCOMMD6-CK. The enzymatic activity assays show that CK activities are inhibited by BbCOMMD6 in a dose-dependent manner. All these data suggest that BbCOMMD6 is involved in energy transduction, via binding to CK and inhibiting activities of CK, and offer first clues to its role as a regulator of CK activities.  相似文献   
992.
刘舒  马正兵  于晓丽  何易 《广西植物》2023,43(10):1932-1940
为解析桃金娘表型性状多样性及其种源间关系,该文以20个不同来源的桃金娘为研究对象,在同质园栽培条件下,对其营养器官和花器官表型性状进行观测,采用方差分析、变异分析、Shannon-Wiener多样性指数分析和聚类分析等方法,探讨不同种源桃金娘表型性状多样性。结果表明:(1)不同种源桃金娘表型性状存在显著差异(P<0.05),Shannon-Wiener多样性指数均值在1.35以上,表型性状多样性丰富。(2)种源内表型性状变异系数均值在10.81%~63.75%之间,种源间的变异系数均值在13.08%~74.04%之间,种源间变异(23.33%)高于种源内变异(19.79%),营养器官变异(29.52%)高于花器官变异(14.06%)。(3)部分性状存在极显著或显著相关性,株高与分枝数呈极显著负相关,而与叶长、叶宽和叶面积等却呈显著正相关。(4)在欧式距离10处,20个种源桃金娘可分为A、B、C三类,A类包含8个种源,该类种源表现为植株高大、分枝少、叶大和花大等特征;B类包含11个种源,该类种源表现为株高中等、叶较大和花中等等特征;C类仅包含1个种源,表现为植株低矮、分枝多、叶小和...  相似文献   
993.
Two kinds of chitosans, namely N-acetylated and N-deacetylated chitosan were prepared by the modified processes. They can dissolve in both acid and alkali solution. 13C NMR was used to study the basic solution of chitosan, and XRD, FT-IR and SEM were used to study the structure of N-acetylated and N-deacetylated chitosan. The result from X-ray diffraction showed that a transformation of crystal structure occurred during the N-acetylation or N-deacetylation process with the decrease of crystallinity and expansion of crystal lattices. FT-IR spectra revealed that the intermolecular and intramolecular hydrogen bonds were destroyed by both treatments and a looser structure was observed by the SEM. The lower crystallinity, the decreased intermolecular interactions, the more disordered and looser structure were easy for the permeation of LiOH/urea aqueous solution and coordinated with the breakage of intermolecular and intramolecular hydrogen bond by LiOH at low temperature, the prepared chitosans dissolved in LiOH/urea/H2O mixture.  相似文献   
994.
We used data on loud duetted and solo songs collected from one habituated polygynous group of black‐crested gibbons (Nomascus concolor jingdongensis) on Mt. Wuliang, Yunnan, to test several hypotheses about the functions of these songs. The major functions proposed for loud gibbon songs include resource defense, mate defense, pairbonding, group cohesion and mate attraction. Duet bouts are generally initiated by adult males, who select the highest trees near to ridges or on steep slopes as singing trees. Such trees facilitate voice transmission and inter‐group communication. Singing trees tended to be located near important food patches and sleeping sites, which supports the resource defense hypothesis. The adult male and two adult females always sang interactively, alternating male phrases with the females' stereotyped great calls, to produce the duets, and females rarely produced great calls if they were more than 30 m from the male. The two females usually produced great calls synchronously during the duet, especially when they were close together. These features support both the mate defense and pairbonding hypotheses. The number of great calls and their degree of synchrony transmit information about spatial relationships and possibly pairbond strength to members to neighboring groups and floating animals. During or after the duet bouts, the adult females and juvenile moved toward to the adult male; and group members maintained a close spatial relationship, which supports the group cohesion hypothesis. Other incidents observed suggest a mate competition role for duets. The adult male always sang when the females started duetting with the subadult male. The subadult male sang solo bouts, but they were not more frequent or longer than bouts initiated by the adult male. Although mate attraction is the likely function of subadult solos, it was not convincingly demonstrated. In conclusion, all hypotheses concerning the function of singing are supported by at least some of the data, and none can be excluded. Am. J. Primatol. 71:539–547, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
995.
Bacterial infections represent serious diseases in aquaculture, rapidly leading to fish death by septicemia. We investigated whether the electrotransfer of green fluorescent protein gene fusion epinecidin-1 (CMV-gfp-epi) DNA into zebrafish muscle could regulate the fish immune response and inhibit bacterial growth. Electroporation parameters such as the number of pulses, voltage, and amount of plasmid DNA were analyzed, and results demonstrated the greatest mRNA expression level of gfp-epi relative to β-actin was obtained with a pulse number of 4, a voltage strength of 100 V/cm, a concentration of DNA of 90 μg/fish, and electroporation for 96 h. In addition, the cytomegalovirus (CMV) promoter exhibited higher activity compared to the mylz promoter in muscle for electrotransfer in zebrafish. GFP fluorescence and gfp-epi mRNA expression in tissues after electroporation were also studied by a polymerase chain reaction, immunohistochemistry, and fluorescence microscopy. gfp-epi expression was significantly correlated with decreased bacterial numbers and immune-related gene expression. These data demonstrate that electroporation of epinecidin-1 might have provoked an inflammatory response that accounts for the improvement in bacterial clearance.  相似文献   
996.
997.
动物孵化酶(hatching enzyme HE)是早期胚胎在特定发育阶段由孵化腺细胞产生和分泌的,在动物早期胚胎孵化中具有关键性作用^[4]。孵化腺细胞(hatching gland cell,HGC)一般为单细胞腺体,是从胚胎发育到特定阶段(孵化前)出现、至胚胎孵出后的特定时期消失的一时性细胞(transient type of  相似文献   
998.
多个抗虫基因转化水稻两用系培矮—64S   总被引:8,自引:0,他引:8  
应用基因枪法对水稻两用系培矮-64S进行了转化。质粒载体pKC-3串联了三个抗虫基因,将其转化成熟胚诱导形成的愈伤组织,共获得33株转基因植株。分别对R0代植株不同的基因进行PCR及Southern blot分析,并对R1代植株进行了PCR分析。结果表明,三个抗虫基因均已整合到水稻基因组并获得稳定遗传。  相似文献   
999.
1000.
滇西南孟连曼信地区早石炭世磷结核中的放射虫   总被引:1,自引:0,他引:1  
滇西南昌宁-孟连构造带下石炭统平掌组火山岩之硅质岩夹层中,存在大量结核,X衍射分析证明,这些结核全部为磷结核。其中一块磷结核经分析,获得放射虫化石7属9种(其中包括一未定种):Albaillella paradoxa Deflandre,Archocyrtium sp.,Robotium validum Cheng,Triaenosphaera sicarius Deflandre,Entactinia herculea Foreman,Entactinia parva Won,Astroentactinia multispinosa(Won),Entactinosphaera inusitata Foreman,Entactiosphaera palimbola Foreman,均属杜内期中期Albaillella paradoxa带。这些磷结核应该沉积在上升洋流形成的洋岛环境,而不是裂谷中。  相似文献   
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