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Natural killer ( NK) cells play an important role in preventing cancer development. NK group 2 member D ( NKG2D) is an activating receptor expressed in the membrane of NK cells. Tumour cells expressing NKG2 DL become susceptible to an immune-dependent rejection mainly mediated by NK cells. The paradoxical roles of transforming growth factor beta ( TGF-β) in regulation of NKG2 DL are presented in many studies, but the mechanism is unclear. In this study, we showed that TGF-β up-regulated the expression of NKG2 DLs in both PC3 and HepG2 cells. The up-regulation of NKG2 DLs was characterized by increasing the expression of UL16-binding proteins ( ULBPs) 1 and 2. TGF-β treatment also increased the expression of transcription factor SP1. Knockdown of SP1 significantly attenuated TGF-β-induced up-regulation of NKG2 DLs in PC3 and HepG2 cells, suggesting that SP1 plays a key role in TGF-β-induced up-regulation of NKG2 DLs. TGF-β treatment rapidly increased SP1 protein expression while not mRNA level. It might be due to that TGF-β can elevate SP1 stability by activating PI3K/ AKT signalling pathway, subsequently inhibiting GSK-3β activity and decreasing the association between SP1 and GSK-3β. Knockdown of GSK-3β further verified our findings. Taken together, these results revealed that AKT/ GSK-3β-mediated stabilization of SP1 is required for TGF-β induced up-regulation of NKG2 DLs. Our study provided valuable evidence for exploring the tumour immune modulation function of TGF-β. [ABSTRACT FROM AUTHOR]

Aphids (Aphididae) are major agricultural pests that cause significant yield losses of crop plants each year by inflicting damage both through the direct effects of feeding and by vectoring harmful plant viruses. Expression of double-stranded RNA (dsRNA) directed against suitable insect target genes in transgenic plants has been shown to give protection against pests through plant-mediated RNA interference (RNAi). Thus, as a potential alternative and effective strategy for insect pest management in agricultural practice, plant-mediated RNAi for aphid control has received close attention in recent years. In this review, the mechanism of RNAi in insects and the so far explored effective RNAi target genes in aphids, their potential applications in the development of transgenic plants for aphid control and the major challenges in this regard are reviewed, and the future prospects of using plant-mediated RNAi for aphid control are discussed. This review is intended to be a helpful insight into the generation of aphid-resistant plants through plant-mediated RNAi strategy. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Small non-protein coding RNAs (ncRNAs) play important roles in development, stress response and other cellular processes. Silkworm is an important model for studies on insect genetics and control of Lepidopterous pests. We have previously identified 189 novel intermediate-size ncRNAs in silkworm Bombyx mori, including 40 ncRNAs that showed altered expression in different developmental stages. Here we characterized the functions of these 40 ncRNAs by measuring their expressions in six tissues of the fifth instar larvae using Northern blot and real-time polymerase chain reaction assays. We identified nine ncRNAs (four small nucleolar RNAs and five unclassified ncRNAs) that were enriched in silk gland, including four ncRNAs that showed silk gland-specific expression. We further showed that three of nine silk gland-enriched ncRNAs were predominantly expressed in the anterior silk gland, whereas another three ncRNAs were highly accumulated in the posterior silk gland, suggesting that they may play different roles in fibroin synthesis. Furthermore, an unclassified ncRNA, Bm-152, exhibited converse expression pattern with its antisense host gene gartenzwerg in diverse tissues, and might regulate the expression of gartenzwerg through RNA-protein complex. In addition, two silk gland-enriched ncRNAs Bm-102 and Bm-159 can be found in histone modification complex, which indicated that they might play roles through epigenetic modifications. Taken together, we provided the first expression and preliminary functional analysis of silk gland-enriched ncRNAs, which will help understand the molecular mechanism of silk gland-development and fibroin synthesis. [ABSTRACT FROM AUTHOR]

Cancer is a global and growing problem. Nodal, which has been showed to be involved in occurrence and development of cancers, is an important embryonic morphogen. The aim of this study was to evaluate the significance of Nodal expression in human cancers based on the published related articles. Online databases were searched to retrieve relevant articles published between 2000 and 2015. The odds ratio (OR) with its 95% confident intervals (CI) were employed to calculate the strength of significance. Finally, a total of 11 articles were screened out, including 801 cancer patients and 372 healthy controls. Nine kinds of cancers were contained, and Nodal was detected in 56.7% of all participants (665/1173). Overall, our result found that Nodal was highly expressed in cancer patients than that in healthy controls, indicating that Nodal expression was significantly associated with cancers progression (OR=21.72, 95% CI=9.94-47.46, P<0.00001). Subgroup analysis showed that Nodal expression was significantly corrected with high WHO grade of human cancers (III+IV versus I+II: OR=2.46, 95% CI=1.63-3.71, P<0.00001). This significant relationship was also found in tumor size, differentiation degree, not observed in gender, age and lymphatic metastasis status of patients with all studied cancers in this meta-analysis. In conclusion, our results demonstrated that Nodal might be implicated in cancer progression, suggesting that it was a potential biomarker and therapeutic target for cancers.