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1.
张虎  曹双  胡昌华 《微生物学报》2017,57(12):1751-1760
丝状真菌是重要的微生物资源,能够产生大量的小分子活性化合物,如β-内酰胺类抗生素、夫西地酸、环孢霉素和他汀类药物等。这些小分子次级代谢产物的生物合成受全局性调控因子的调控,除丝状真菌中已发现的Lae A外,还存在一类具有Velvet结构域的特殊调控因子,它们在丝状真菌的生长发育和次级代谢调控中发挥着重要的作用。本文综述了丝状真菌Velvet家族蛋白(Ve A、Vel B、Vos A和Vel C)的结构特征及其对有性生殖、无性生殖和次级代谢产物合成等方面的调控作用,并探讨了可能的分子调控机制通路,为揭示次级代谢调控网络和激活沉默基因产生新型结构的化合物提供一定的参考价值。  相似文献   
2.
In this study, we describe the process of pedicle and first antler growth in Iberian red deer (Cervus elaphus hispanicus) and document relationships among body development, maternal milk supply and composition, and maternal weight on the length of first antlers. Antler length of 53 males of Iberian red deer was measured every 2 weeks from birth to 20 months of age. Deer weight, age, and the date of occurrence of the major events during the antler growth cycle were also recorded. The first evidence of pedicle development occurred when the animals were 38.0 ± 0.6 weeks old and weighed 60.7 ± 0.9 kg. Antler cleaning took place at a mean age of 63.8 ± 0.7 weeks and a mean weight of 91.5 ± 1.8 kg. The antler growth period lasted 16.7 ± 0.4 weeks, and the cleaning period lasted 5.1 ± 0.4 weeks. First antler growth followed a sigmoid curve, reaching a final length of 38.3 ± 1.0 cm. Antler length was positively correlated with body weight during the antler growth cycle. Additionally, the final length of the first antler was related to total milk yield, date of antler growth initiation, body weight at 6 months of age, and the antler growth time interval.  相似文献   
3.
 We have identified an engrailed-class (en-class) gene and determined the distribution pattern of its protein during embryogenesis in a member of the Onychophora. The results of this work add to our understanding of the evolution of development and in addition, they contribute information toward clarifying the phylogenetic position of this group. We observe transient expression in a portion of each developing segment. By the time limbs have formed, segmental expression of en-class protein is restricted to the mesoderm. This pattern shares important spatio-temporal characteristics with those of Annelida and Arthropoda, both of which have members that express en-class genes segmentally in mesoderm and ectoderm. Received: 30 January 1997 / Accepted: 17 July 1997  相似文献   
4.
张明海 《生物技术》2003,13(6):48-49
控制光照周期中的光照强度(I)和光照/黑暗比率(L/D)对鹿茸的生长发育影响的作用明显,其中,在I=300lx和L/D=1.00-3.00时,鹿茸的生长发育最好。此外,鹿体内的性腺激素对鹿茸的生长发育有明显的作用。  相似文献   
5.
The velvet regulators VosA and VelB are primarily involved in spore maturation and dormancy. Previous studies found that the VosA-VelB hetero-complex coordinates certain target genes that are related to fungal differentiation and conidial maturation in Aspergillus nidulans. Here, we characterized the VosA/VelB-inhibited developmental gene vidD in A. nidulans. Phenotypic analyses demonstrated that the vidD deleted mutant exhibited defect fungal growth, a reduced number of conidia, and delayed formation of sexual fruiting bodies. The deletion of vidD decreased the amount of conidial trehalose, increased the sensitivity against heat stress, and reduced the conidial viability. Moreover, the absence of vidD resulted in increased production of sterigmatocystin. Together, these results show that VidD is required for proper fungal growth, development, and sterigmatocystin production in A. nidulans.  相似文献   
6.
The aims of this study were to describe first antler growth rate and the factors affecting it. Growth rate reached a peak in week 14. Mean first antler growth rate during the whole growing period was 1.95 ± 0.05 cm/week. Lactation influenced antler growth rate as this was positively affected by total protein yield, while antlers grew at a lower rate the later they started to grow.  相似文献   
7.
For many researchers, next generation sequencing data holds the key to answering a category of questions previously unassailable. One of the important and challenging steps in achieving these goals is accurately assembling the massive quantity of short sequencing reads into full nucleic acid sequences. For research groups working with non-model or wild systems, short read assembly can pose a significant challenge due to the lack of pre-existing EST or genome reference libraries. While many publications describe the overall process of sequencing and assembly, few address the topic of how many and what types of reads are best for assembly. The goal of this project was use real world data to explore the effects of read quantity and short read quality scores on the resulting de novo assemblies. Using several samples of short reads of various sizes and qualities we produced many assemblies in an automated manner. We observe how the properties of read length, read quality, and read quantity affect the resulting assemblies and provide some general recommendations based on our real-world data set.  相似文献   
8.
曲霉(Aspergillus)是应用于工业生产的一类重要微生物,它与人类生活及医药卫生等方面密切相关。分生孢子的形成是曲霉无性繁殖的主要方式,它是个复杂的过程,需要多个基因参与调控,且分生孢子的形成与次级代谢产物的生物合成有密切的关系。本文综述了曲霉分生孢子形成的调控模式,简述了曲霉中连接无性发育和曲霉毒素生物合成的G-蛋白信号通路,及既参与发育调控又参与曲霉次级代谢调控的Velvet蛋白家族,可为其他丝状真菌的研究提供理论指导,对工业生产也有很重要的意义。  相似文献   
9.
天津近郊番茄病毒类型的研究   总被引:1,自引:0,他引:1  
应用ELISA间接法检测出天津近郊番茄上至少有9种病毒类型。且首次检测出国内在番茄上尚未报道的番茄黑环病毒(TBRV)、绒毛烟斑驳病毒(VTMoV)。经生物学测定还分离出番茄上表现枯斑型的86-125和在豇豆上产生大红斑的86-95-15均与13种抗血清呈阴性反应的杆状待测病毒。  相似文献   
10.
2019年12月10日至2020年1月,在上海市浦东新区南汇东滩滴水湖水域持续观察和拍摄到一种鸭科鸟类。经查文献并与所观察记录到的鸟类进行形态特征比对,鉴定为丝绒海番鸭(Melanitta fusca),为中国鸟类分布新记录种。  相似文献   
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