丝束蛋白（fimbrin）是肌动蛋白细胞骨架的调节因子，参与并控制多种组织和细胞的生理生化和发育过程。然而，fimbrin在对病原菌防御中，特别是在小麦抗条锈病中的作用研究匮乏，其机制尚待阐明。本研究以小麦品种水源11（Suwon 11）与条锈菌（Puccinia striiformis f. sp. tritici，Pst）生理小种CYR23组成非亲和互作，与生理小种CYR31组成成亲和互作，利用实时荧光定量 PCR 技术（qRT-PCR）对TaFIM1基因参与小麦抗条锈病的功能进行初步分析；对在非生物胁迫和施用外源激素处理TaFIM1基因的表达特征进行分析；通过病毒诱导的基因沉默（BSMV-VIGS）技术，验证TaFIM1在小麦抗条锈病中的功能。获得以下研究结果：TaFIM1在非亲和互作中的表达量显著上调，且在48 h表达量达到峰值，是对照0 h的6.0倍；在亲和互作中，TaFIM1的表达量无明显变化。TaFIM1能够响应不同非生物胁迫，在高温（Hot）、低温（Cool）、盐（NaCl）和干旱（PEG6000）胁迫下诱导TaFIM1基因表达量上调。BSMV-VIGS试验结果显示，借助大麦条纹花叶病毒对TaFIM1基因进行诱导沉默。对沉默成功的小麦植株分别接种条锈菌CYR23和CYR31。在非亲和互作中，沉默植株的抗病性降低，叶片上出现少量的夏孢子堆；在亲和互作中，与对照相比，叶片上的夏孢子堆数量增加，沉默植株的感病性增强。组织学观察发现，在48 h和120 h，TaFIM1沉默植株叶片中菌丝分支数和菌丝长度高于对照，在120 h基因沉默植株叶片中菌落面积显著高于对照组，表明TaFIM1沉默后小麦植株与对照相比感病性增强，进一步说明TaFIM1参与植物的抗病性。因此，TaFIM1与植物抗病性相关，在小麦抵抗条锈病的侵染过程中响应正调控作用。本研究为理解fimbrin在小麦中的作用提供了新的见解。

MicroRNAs (miRNAs) are small, single stranded, non-coding RNA molecules, about 19–25 nucleotides in length, which regulate the development and functions of reproductive system of mammal. To discover novel miRNAs and identify the differential expression of them in ovine ovary and testis tissues, the study constructed two libraries by using next-generation sequencing technologies (Solexa high-throughput sequencing technique). As a result, 9 321 775 and 9 511 538 clean reads were obtained from the ovary and testis separately, which included 130 562 (90 genes of ovary) and 56 272 (85 genes of testis) of known miRNAs and 486 potential novel miRNAs reads. In this study, a total of 65 conserved miRNAs were significantly differentially expressed (P<0.01) between the two samples. Among them, 28 miRNAs were up-regulated and 3 miRNAs were down-regulated on ovary compared with testis. In addition, the known miRNAs with the highest expression level (5 miRNAs) and 30 novel miRNAs with the functions related to reproduction were validated using the real-time quantitative RT-PCR. Moreover, the gene ontology (GO) annotation and Kyoto encyclopedia of genes and genomes (KEGG) pathway analysis showed that differentially expressed miRNAs were involved in ovary and testis physiology, including signal transduction, gonad development, sex differentiation, gematogenesis, fertilization and embryo development. The results will be helpful to facilitate studies on the regulation of miRNAs during ruminant reproduction.

Somatic hybridization is performed to obtain significant cytoplasmic male sterility (CMS) lines, whose CMS genes are derived either from the transfer of sterile genes from the mitochondrial genome of donor parent to the counterpart of receptor or production of new sterile genes caused by mitochondrial genome recombination of the biparent during protoplast fusion. In this study, a novel male sterile line, SaNa-1A, was obtained from the somatic hybridization between Brassica napus and Sinapis alba. The normal anther development of the maintainer line, SaNa-1B, and the abortive process of SaNa-1A were described through phenotypic observations and microtome sections. The floral organ of the sterile line SaNa-1A was sterile with a shortened filament and deflated anther. No detectable pollen grains were found on the surface of the sterile anthers. Semi-thin sections indicated that SaNa-1A aborted in the pollen mother cell (PMC) stage when vacuolization of the tapetum and PMCs began. The tapetum radically elongated and became highly vacuolated, occupying the entire locule together with the vacuolated microspores. Therefore, SaNa-1A is different from other CMS lines, such as ogu CMS, pol CMS and nap CMS as shown by the abortive process of the anther.

Mitochondrial malate dehydrogenase (mMDH) and citrate synthase (CS) are sequential enzymes in Krebs cycle. mMDH, CS and the complex between mMDH and CS (mMDH+CS) were treated with nitric oxide solution. The roles of notric oxide (NO) on the secondary structures and the interactions between mMDH and CS were studied using circular diehroism (CD) and Fourier transform surface plasmon resonance (FT-SPR), respectivley. The effects of NO on the activities of mMDH, CS and mMDH+CS were also studied. And the regulations by NO on mMDH and CS were simulated by PyMOL software. The results of SPR confirmed that strong interaction between mMDH and CS existed and NO could significantly regulate the interaction between the two enzymes. NO reduced the mass percents of α-helix and increased that of random in mMDH, CS and mMDH+CS. NO increased the activities of CS and mMDH+CS, and inhibited the activity of mMDH. Graphic simulation indicated that covalent bond was formed between NO and Asn242 in active site of CS. However, there was no direct bond between NO and mMDH. The increase in activity of mMDH+CS complex depended mostly on the interaction between NO and CS. All the results suggested that the regulations by NO on the activity and interaction between mMDH and CS were accord with the changes in mMDH, CS and mMDH+CS caused by NO.