Identification and characterization of microRNAs related to salt stress in broccoli, using high-throughput sequencing and bioinformatics analysis

BACKGROUND: MicroRNAs (miRNAs) are a new class of endogenous regulators of a broad range of physiological processes, which act by regulating gene expression post-transcriptionally. The brassica vegetable, broccoli (Brassica oleracea var. italica), is very popular with a wide range of consumers, but environmental stresses such as salinity are a problem worldwide in restricting its growth and yield. Little is known about the role of miRNAs in the response of broccoli to salt stress. In this study, broccoli subjected to salt stress and broccoli grown under control conditions were analyzed by high-throughput sequencing. Differential miRNA expression was confirmed by real-time reverse transcription polymerase chain reaction (RT-PCR). The prediction of miRNA targets was undertaken using the Kyoto Encyclopedia of Genes and Genomes (KEGG) Orthology (KO) database and Gene Ontology (GO)-enrichment analyses. RESULTS: Two libraries of small (or short) RNAs (sRNAs) were constructed and sequenced by high-throughput Solexa sequencing. A total of 24,511,963 and 21,034,728 clean reads, representing 9,861,236 (40.23%) and 8,574,665 (40.76%) unique reads, were obtained for control and salt-stressed broccoli, respectively. Furthermore, 42 putative known and 39 putative candidate miRNAs that were differentially expressed between control and salt-stressed broccoli were revealed by their read counts and confirmed by the use of stem-loop real-time RT-PCR. Amongst these, the putative conserved miRNAs, miR393 and miR855, and two putative candidate miRNAs, miR3 and miR34, were the most strongly down-regulated when broccoli was salt-stressed, whereas the putative conserved miRNA, miR396a, and the putative candidate miRNA, miR37, were the most up-regulated. Finally, analysis of the predicted gene targets of miRNAs using the GO and KO databases indicated that a range of metabolic and other cellular functions known to be associated with salt stress were up-regulated in broccoli treated with salt. CONCLUSION: A comprehensive study of broccoli miRNA in relation to salt stress has been performed. We report significant data on the miRNA profile of broccoli that will underpin further studies on stress responses in broccoli and related species. The differential regulation of miRNAs between control and salt-stressed broccoli indicates that miRNAs play an integral role in the regulation of responses to salt stress. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12870-014-0226-2) contains supplementary material, which is available to authorized users

A dual-role hierarchical RBAC extended security model based on department attributes and its application

In order to overcome the problems of the classic RBAC model, such as user identity cannot be verified, role assignment conflicts, permission leakage, complicated roles and permissions configuration, etc., this paper proposes a dual-role hierarchical RBAC extended security model based on department attributes. Firstly, based on the identity authentication mechanism, the legality of the user identity used by the system and its department attributes are authenticated, and the legal identity users are associated with their departments. Then, the roles were divided into responsibility roles and system roles in the classic RBAC model, which are defined by the system administrator is responsible for configuring system roles according to the permission control requirements of resources and operations in the system. The person in charge of the department to which the user belongs configures the role for the user according to the actual work responsibilities of each user, and the person in charge of the department is responsible for the relationship between the role and the system. Finally, this dual-role hierarchical RBAC extended security model based on department attributes is applied to the authority management scheme of a power grid business system. The security analysis and practical results show that this dual-role hierarchical RBAC extended security model based on department attributes is a system rights management solution with strong security and practicability

Radioactive ¹²⁵I seed inhibits the cell growth, migration, and invasion of nasopharyngeal carcinoma by triggering DNA damage and inactivating VEGF-A/ERK signaling.

Although radiotherapy technology has progressed rapidly in the past decade, the inefficiency of radiation and cancer cell resistance mean that the 5-year survival rate of patients with nasopharyngeal carcinoma (NPC) is low. Radioactive (125)I seed implantation has received increasing attention as a clinical treatment for cancers. Vascular endothelial growth factor-A (VEGF-A) is one of the most important members of the VEGF family and plays an important role in cell migration through the extracellular-signal-regulated kinase (ERK) pathway. Here we show that radioactive (125)I seeds more effectively inhibit NPC cell growth through DNA damage and subsequent induction of apoptosis, compared with X-ray irradiation. Moreover, cell migration was effectively inhibited by (125)I seed irradiation through VEGF-A/ERK inactivation. VEGF-A pretreatment significantly blocked (125)I seed irradiation-induced inhibition of cell migration by recovering the levels of phosphorylated ERK (p-ERK) protein. Interestingly, in vivo study results confirmed that (125)I seed irradiation was more effective in inhibiting tumor growth than X-ray irradiation. Taken together, these results suggest that radioactive (125)I seeds exert novel anticancer activity by triggering DNA damage and inactivating VEGF-A/ERK signaling. Our finding provides evidence for the efficacy of (125)I seeds for treating NPC patients, especially those with local recurrence

Irradiation models of ¹²⁵I seeds.

<p>(A) <i>In vitro</i> model, eight ¹²⁵I seeds were evenly taped around a 30-mm diameter circumference, with one ¹²⁵I seed placed in the center. (B) <i>In vivo</i> model, a transverse CT scanning was performed on mice, and the dose distribution was calculated by TPS and the GTV (the red circle) should be kept inside the 90% isodose curve (blue one) in every plan. 8 Seeds were implanted into different position by the needle (the three yellow vertical lines) according to TPS.</p