棉花MicroRNA研究进展

概述了miRNA的结构特点、生物合成、作用机理、功能以及棉花miRNAs研究等方面的研究进展。     

植物非编码RNA及其在甜菜中的应用研究

非编码RNA是在真核生物中发现的具有调控功能的RNA,能够以各种方式参与植物的生长发育、信号转导以及逆境胁迫等生命过程。甜菜是我国重要的糖料作物,最近研究发现非编码RNA中的miRNA能够以多种方式参与到甜菜应对盐胁迫、干旱胁迫及养分胁迫的应答中。另外,在病毒侵染甜菜过程中发现非编码RNA起到重要作用。因此研究甜菜非编码RNA对于甜菜的种植和品种改良具有重要意义。本文简要综述了目前研究较多的miRNA、lncRNA和circRNA的产生方式及调控机制,并介绍了miRNA参与甜菜逆境胁迫和lncRNA影响甜菜春化机制的一些研究,旨在对未来甜菜非编码RNA的进一步研究提供理论指导。     

羽衣甘蓝红色系叶片形成相关microRNAs的鉴定及分析

为了在转录后水平上探索microRNAs(miRNAs)对羽衣甘蓝红色系叶片形成的调控作用,以红和白色系的羽衣甘蓝品种‘紫鸽’‘白鸽’为研究试材,利用高通量测序技术分别对其紫红(Bo-P)和白色(Bo-W)心叶进行了小RNA(sRNA)测序分析。结果表明:1)共鉴定出77个保守miRNAs和33个新miRNAs在Bo-P和Bo-W文库中差异表达;2)基于miRNAs的差异表达和相应靶基因的注释结果,筛选出2个可能与红色系叶片中花青苷生物合成有关的DEMs(miR828和miR858-3);3)荧光定量PCR(qRT-PCR)结果显示与高通量测序结果基本一致,其中2次结果显示miR828在紫红和白色心叶中表达量的差异倍数均很大。基于上述结果,初步确定miR828和miR858-3(特别是miR828)在转录后水平对羽衣甘蓝叶片红色系表型的形成起到关键调控作用,该结果将为今后深入揭示羽衣甘蓝叶色的分子调控机制提供理论基础和新视角。     

Differential expression of microRNAs in avian leukosis virus subgroup J-induced tumors

Avian leukosis virus subgroup J (ALV-J) has become pandemic and induced serious clinical outbreaks in chickens in China. In particular, ALV-J induced various clinical tumors in infected chickens, which caused enormous economic losses to poultry. In this study, an infectious clone from an epidemic ALV-J Chinese isolate designated HLJ09SH01 was constructed and rescued. The rescued virus (named rHLJ09SH01) was inoculated into specific-pathogen-free (SPF) layer chickens, and infected chickens were observed for 238 days to explore the oncogenicity of rHLJ09SH01. As a result, 57.9% of rHLJ09SH01-infected chickens produced tumors. Accumulating evidence shows that microRNAs (miRNAs) have a close relationship with tumorigenesis. To gain more insight into the tumorigenesis of ALV-J, a miRNA microarray was performed as part of an investigation of changes in host miRNA expression in a liver tumor from ALV-J infected chickens. The results showed that four miRNAs were significantly differentially expressed; these data were verified using real-time PCR. Bioinformatics analysis showed the differentially expressed miRNAs to be involved in some tumorigenesis-related signaling pathways, such as the MAPK signaling pathway and the Wnt signaling pathway, which may represent a possible signaling pathway that was involved in the ALV-J-induced tumorigenesis.     

miRNAs对骨骼肌调控的研究进展

microRNAs（miRNAs）是生物体内自然存在的一类长度约为22 nt的小分子非编码RNA，能够通过与靶基因mRNA 3'UTR不完全互补配对，降解靶基因mRNA或抑制其翻译，在转录后水平调控基因的表达，进而广泛参与调控机体生长、发育、疾病等多个生物学过程。骨骼肌约占人体体重的40%，是动物体维持正常生长发育必不可少的组成部分。miRNAs通过靶向骨骼肌发育、再生与疾病过程的关键因子，进而发挥调控作用。作为骨骼肌疾病的重要调控因子，miRNAs已成为肌肉相关疾病的检测标志物和靶向诊疗药物。近年来，随着对miRNAs研究的深入，有关miRNAs对骨骼肌调控的研究已成为生命科学领域的研究热点。作者综述了miRNAs参与调控骨骼肌细胞增殖、分化、再生与疾病等方面的研究进展，旨在为治疗肌肉疾病及提高畜禽肉品质提供理论依据。     

Influence on Cellular Signal Transduction Pathway in Dairy Cow Mammary Gland Epithelial Cells by Galactopoietic Compound Isolated from Vaccariae segetalis

The galactopoietic mechanism of Vaccaria segetalis is still unknown. Understanding dibutyl phthalate (DBP) separated from Vaccaria segetalis on the expression of lactation signal transduetion genes of mammary gland epithelial cells, including prlr, erα, akt1, socs2, pparγand elf5, will be helpful to reveal the molecular mechanism. Western blot and qRTPCR were used to study the change of prlr, erα, akt, socs2, pparγ, and elf5 expression at mRNA and protein level. Colocalization expression of prolactin receptor (PRLR) and estrogen receptor α (ERα) was observed by immunofluoreseence;the expression changes of miRNAs (21, 125b, 143, and 195) and the secretion of β-casein and lactose were detected byqRT-PCR and RP-HPLC. The results showed that Vaccaria segetalis active compound had similar fuctions as estrogen and/or prolactin (PRL) in dairy cow mammary gland epithelial cells (DCMECs), increased the expressions of prlr, erα, akt1,and elf5 genes, while repressed ppaγ expressions. DBP promoted socs2 mRNA expression, but its protein expressionswere repressed. Furthermore, both DBP and PRL could repress the expressions of miRNA-125b, miRNA-143 and miRNA-195 in DCMECs. DBP could repress the expression of miRNA-21, while the influence of PRL on miRNA-21 was not certain.DBP could promote the lactation ability of DCMECs by regulating the ER and PRLR cellular signal transduction pathway.     

小RNA测序揭示miRNAs在油棕合子胚发育中的作用

油棕是世界上产油效率最高的热带木本油料作物,其棕榈油产量与合子胚发育密切相关.油棕的合子胚发育是一个系统且复杂的生物过程,其中涉及许多基因的精确调控.MicroRNAs(miRNAs)是重要的信号分子,调节植物的各种发育过程.一些miRNAs已经被整合到基因调控网络中协调植物胚发育的可塑性,但对于其在油棕合子胚发育过程...     

棉花盐胁迫下叶片miRNAs的鉴定与分析

microRNAs(miRNAs)是一类21~24个核酸长度的非编码小分子RNA(sRNA,small RNA),通过介导目标mRNA的切割或者抑制翻译来调节植物基因的表达。本文利用200 mmol·L-1NaCl分别处理3叶期耐盐品系早熟长绒7号和盐敏感品系南丹巴地大花4 h,构建了4个小RNA文库并测序。以雷蒙德氏棉(Gossypium raimondii L.)D5基因组和本实验室陆地棉(Gossypium hirsutum L.)盐胁迫转录组测序拼接得到的序列作为参考,共发现360个miRNA,包括308个保守的miRNA和52个可信度高的新miRNA。2个品系共出现94个差异表达的miRNA,表达模式可分为2大类,筛选出20个候选miRNA。KEGG(Kyoto encyclopedia of genes and genomes)分析表明,耐盐品系显著富集的信号通路是抗原加工过程,而盐敏感品系显著富集的是生物碱合成途径。     

干旱胁迫下香蕉miRNAs的表达分析

以干旱驯化和未驯化的香蕉幼苗为研究材料,采用实时荧光定量PCR方法检测干旱胁迫过程中6个miRNAs的表达变化。结果表明:6个miRNAs在所有香蕉幼苗的干旱胁迫响应过程中均有表达,但其表达模式存在差异,在直接干旱处理下,mi R156k、mi R160a、mi R162a、mi R164a、mi R166d的表达均呈现升高-降低的趋势,mi R397b的表达则呈现升高-降低-升高-降低的趋势;在驯化后干旱处理下,mi R156k、mi R162a、mi R166d、mi R397b的表达均呈现升高-降低的趋势,mi R160a、mi R164a的表达则呈现升高-降低-升高-降低的趋势。干旱胁迫响应过程中(除处理后第10天外),驯化后的香蕉幼苗中miRNAs的表达量基本上高于未驯化香蕉幼苗中miRNAs的表达量,同时还发现mi R160a和mi R164a的表达量都非常高。上述研究结果将为香蕉干旱胁迫应答研究奠定基础。