MicroRNAs (miRNAs) are known to play important roles in plant growth and stress response. Heat stress is a severe abiotic stresses by adversely affecting plant growth and yield. To identify heat-responsive miRNAs at the genome-wide level in rice (Oryza sativa), we constructed two small RNA libraries from young panicles treated or not with heat conditions. Ion torrent sequencing of the two libraries identified 294 known miRNAs and 539 novel miRNAs. Differential expression analysis showed that 26 miRNAs were downregulated and 21 miRNAs were upregulated in response to heat stress. Among them, five heat-responsive miRNAs, including miR162b, miR529a-p5, PC-5P-62245-9, miR171b and miR169n, were validated by quantitative real-time polymerase chain reaction. A total of 44 target genes of the differentially expressed miRNAs were predicted. These target genes are most significantly overrepresented in the cell growth process. The results demonstrated that rice miRNAs play critical roles in the heat stress response. This study opens up a new avenue for understanding the regulatory mechanisms of miRNAs involvement in the heat stress response in rice.

Lipases are ubiquitous enzymes in nature, which play a crucial role in fat metabolism by catalyzing the hydrolysis of triacylglycerol to free fatty acids and glycerol. However, reports concerning insect lipase are rare. In this study, we studied the expression and activity of a lipase-related protein from Antheraea pernyi (ApLRP). Recombinant ApLRP was expressed in Escherichia coli cells and used to raise rabbit anti-ApLRP polyclonal antibodies. ApLRP mRNA and protein expression were abundant in the midgut and malpighian tubules, respectively. After challenge with four different microorganisms (E. coli, Beauveria bassiana, Micrococcus luteus and nuclear polyhedrosis virus), the expression levels of ApLRP mRNA in midgut were inducted significantly compared with the control. The different pathogens induced different ApLRP gene expression patterns. The optimum temperature and pH for the enzyme's activity were 35°C and 7.0, respectively. ApLRP activity was stimulated in the presence of Mg2+, Na+, Ca2+ and b-mercaptoethanol; while Zn2+, Cu2+ and Fe3+ inhibited its activity. Detergents such as SDS, glycerol and Tween-20 increased the lipase activity by 20-30%. Our results indicated that ApLRP might play an important role in the innate immunity of insects.

Lipoxygenase (LOX) activity is closely related to wheat processing and storage quality. In the present research, ten wheat cultivars were used to compare the effects of genotype, location, year, and their interactions on the LOX activity. Furthermore, 123 wheat cultivars were evaluated for LOX activity with 192 simple sequence repeat (SSR) markers and to identify elite alleles related to LOX activity. The results indicated that LOX activity was highly affected by genotype (variety) than that by the location. A total of 22 SSR molecular marker loci with a significant or very significant correlation with LOX activity were identified on performing association analysis. In 3 years, only one molecular marker locus associated with LOX activity was detected (WMC488); in 2 years, seven molecular marker loci were detected, while in only 1 year, the other 14 molecular marker loci were detected. A total of 7 and 6 marker loci significantly related to LOX activity accounting for 31.2% and 27.2%, respectively, were located in homologous groups 4 and 5, and group 7. This research provided the theoretical basis and the markers for molecular-assisted wheat breeding that facilitate the breeding process in the processing and storage quality of grains.

ABSTRACT. Karyopherins, including alpha and beta types, are transport proteins in the eukaryotic cell that carry cargoes across nuclear pore complexes into or out of the nucleus. In this study, full open reading frames of one beta and three alpha types of karyopherin were cloned from cDNA of the domestic silkworm (Bombyx mori). The one beta and three alpha types' open reading frames were 2661, 1563, 1515, and 1551 base pairs long, respectively, and coded 886, 520, 504, and 516 amino acids, respectively. The alphas all had one importin-beta-binding (IBB) domain, and eight, four, or seven armadillo/beta-catenin-like repeats. The beta had 19 HEAT repeat domains, which constructed one importin-beta-N-terminal domain and one IBB domain. The recombinant proteins were expressed in Escherichia coli cells. The molecular weight of the beta type was approximately 100 kDa, and the alphas weighed approximately 60 kDa. Phylogenic tree construction revealed that the alphas could be classified into three known karyopherin-alpha subfamilies. We detected mRNA of the four karyopherins in normal 3rd day of 5th instar larvae, and in larvae injected with Grampositive bacteria, Gram-negative bacteria, viruses, and fungi using real- time fluorescence quantitative reverse transcriptase-polymerase chain reaction, and found that the four karyopherins were widely distributed, but their expression levels were related to tissues type, the microbe injected, and the time point.