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Background Brassica napus is an important oilseed crop that offers a considerable amount of biomass for global vegetable oil production. The establishment of an efficient genetic transformation system with a convenient transgenic-positive screening method is of great importance for gene functional analysis and molecular breeding. However, to our knowledge, there are few of the aforementioned systems available for efficient application in B. napus. Results Based on the well-established genetic transformation system in B. napus, five vectors carrying the red fluorescence protein encoding gene from Discosoma sp. (DsRed) were constructed and integrated into rapeseed via Agrobacterium-mediated hypocotyl transformation. An average of 59.1% tissues were marked with red fluorescence by the visual screening method in tissue culture medium, 96.1% of which, on average, were amplified with the objective genes from eight different rapeseed varieties. In addition, the final transgenic-positive efficiency of the rooted plantlets reached up to 90.7% from red fluorescence marked tissues, which was much higher than that in previous reports. Additionally, visual screening could be applicable to seedlings via integration of DsRed, including seed coats, roots, hypocotyls and cotyledons during seed germination. These results indicate that the highly efficient genetic transformation system combined with the transgenic-positive visual screening method helps to conveniently and efficiently obtain transgenic-positive rapeseed plantlets. Conclusion A rapid, convenient and highly efficient method was developed to obtain transgenic plants, which can help to obtain the largest proportion of transgene-positive regenerated plantlets, thereby avoiding a long period of plant regeneration. The results of this study will benefit gene functional studies especially in high-throughput molecular biology research.

Calmodulin-like proteins (CMLs) have been shown to play key regulatory roles in calcium signaling in plants. However, few bona-fide CMLs binding proteins have been characterized in rice, a monocot model plant. Here, through large-scale screening of a yeast-two hybrid (Y2H) cDNA library with OsCML16 as a bait, six new putative interacting partners of OsCML16 were discovered and confirmed by both pairwise Y2H and bimolecular fluorescence complementation (BiFC) assays. Interestingly, the in vitro peptide-binding assays manifested that OsERD2 could bind both OsCaM1 and OsCML16 whereas other five target proteins could specifically bind OsCML16 but not OsCaM1. Furthermore, Ca2+ and TFP, a calmodulin (CaM) antagonist, were involved in the ABA-induced transcription of OsCML16 and its target genes, and they were also obviously induced by cold, drought, and salt stresses. Taken together, our new findings have provided the basis for the novel signaling pathways of OsCML16 in the abiotic stress response in rice.

Fatty acids (FAs) have been implicated in signaling roles in plant defense responses. We previously reported that mutation or RNAi-knockdown (OsSSI2-kd) of the rice OsSSI2 gene, encoding a stearoyl acyl carrier protein FA desaturase (SACPD), remarkably enhanced resistance to blast fungus Magnaporthe oryzae and the leaf-blight bacterium Xanthomonas oryzae pv. oryzae (Xoo). Transcriptomic analysis identified six AAA-ATPase family genes (hereafter OsAAA-ATPase1&ndash, 6) upregulated in the OsSSI2-kd plants, in addition to other well-known defense-related genes. Here, we report the functional analysis of OsAAA-ATPase1 in rice&rsquo, s defense response to M. oryzae. Recombinant OsAAA-ATPase1 synthesized in Escherichia coli showed ATPase activity. OsAAA-ATPase1 transcription was induced by exogenous treatment with a functional analogue of salicylic acid (SA), benzothiadiazole (BTH), but not by other plant hormones tested. The transcription of OsAAA-ATPase1 was also highly induced in response to M. oryzae infection in an SA-dependent manner, as gene induction was significantly attenuated in a transgenic rice line expressing a bacterial gene (nahG) encoding salicylate hydroxylase. Overexpression of OsAAA-ATPase1 significantly enhanced pathogenesis-related gene expression and the resistance to M. oryzae, conversely, RNAi-mediated suppression of this gene compromised this resistance. These results suggest that OsAAA-APTase1 plays an important role in SA-mediated defense responses against blast fungus M. oryzae.

C1orf61 is a specific transcriptional activator that is highly up-regulated during weeks 4-9 of human embryogenesis, the period in which most organs develop. We have previously demonstrated that C1orf61 acts as a tumor activator in human hepatocellular carcinoma (HCC) tumorigenesis and metastasis. However, the underlying molecular mechanisms of tumor initiation and progression in HCC remain obscure. In this study, we demonstrated that the pattern of C1orf61 expression was closely correlated with metastasis in liver cancer cells. Gene expression profiling analysis indicated that C1orf61 regulated diverse genes related to cell growth, migration, invasion and epithelial-mesenchymal transition (EMT). Results showed that C1orf61 promotes hepatocellular carcinoma metastasis by inducing cellular EMT in vivo and in vitro. Moreover, C1orf61-induced cellular EMT and migration are involved in the activation of the STAT3 and Akt cascade pathways. In addition, C1orf61 expression improved the efficacy of the anticancer therapy sorafenib in HCC patients. For the first time, we report a regulatory pathway by which C1orf61 promoted cancer cell metastasis and regulated the therapeutic response to sorafenib. These findings increased our understanding of the molecular events that regulate metastasis and treatment in HCC.