ABSTRACT. Glycine betaine is an important quaternary ammonium compound that is produced in response to several abiotic stresses in many organisms. The synthesis of glycine betaine requires the catalysis of betaine aldehyde dehydrogenase (BADH), which can convert betaine aldehyde into glycine betaine in plants, especially in halotolerant plants. In this study, we isolated the full-length cDNA of BADH from Suaeda corniculata (ScBADH) using reverse transcriptase-polymerase chain reaction and rapid amplification of cDNA ends. Next, we analyzed the expression profile of ScBADH using real-time PCR. The results showed that ScBADH expression was induced in the roots, stems, and leaves of S. corniculata seedlings under salt and drought stress. Next, ScBADH was overexpressed in Arabidopsis, resulting in the transgenic plants exhibiting enhanced tolerance over wild-type plants under salt and drought stress. We then analyzed the levels of glycine betaine and proline, as well as superoxide dismutase (SOD) activity, during salt stress in WT and transgenic Arabidopsis. The results indicated that overexpression of ScBADH produced more glycine betaine and proline, and increased SOD activity under NaCl treatment. Our results suggest that ScBADH might be a positive regulator in plants during the response to NaCl.

Protein disulphide isomerase family A3 (PDIA3) has an activity of thioredoxin, widely expressed in multiple tissues and involved in multiple cellular processes. It was recently found in human and mouse sperm cells and could affect sperm-egg fusion. Therefore, the present investigation aims to identify PDIA3 mRNA and protein in rat testis and sperm cells. Rat PDIA3 cDNA was cloned by RT-PCR. The cRNA riboprobe was transcribed from PDIA3 cDNA and was used to display PDIA3 mRNA location in rat testes by in situ hybridization. PDIA3 protein distribution was also observed in testis and sperm cells by immunohistochemistry and immunocytochemistry, respectively. The rat PDIA3 transcript and protein were localized in the cells from spermatocytes to the spermatozoa phases of rat testes, mostly in the pachytene spermatocytes. PDIA3 protein was also observed on the intact sperm membrane including the tail. The rat PDIA3 gene is transcribed and translated through the whole spermatogenesis process, and the PDIA3 protein is spread all over the sperm cell membrane. The results provide some primary information about PDIA3 in testis and sperm for further study on PDIA3 function in rat spermatogenesis and sperm-egg fusion.

Career situation of first and presenting author: Student for a master or a PhD.IntroductionLong non-coding RNAs (lncRNAs) have drawn increasing attention because of the pivotal roles which they play in various types of autoimmune diseases, including rheumatoid arthritis (RA). LncRNA HOTAIR is a crucial lncRNA function as an oncogene in multiple cancers. Fibroblast-like synoviocytes (FLSs), a prominent component of hyperplastic synovial pannus tissue, are critical to synovial aggression and joint destruction in RA. However, the functions of lncRNA and the potential mechanisms remain to be further elucidated in FLSs of RA patients.ObjectivesOur present study aimed to investigate the expression and roles of lncRNA HOTAIR in RA-FLSs and explore its possible mechanism.MethodsFLSs were cultured from synovial tissues of join. LncRNA and mircoRNA expression profiles in FLSs were screened by microarrays, and then we validated the results by Real-time Quantitative polymerase chain reaction (qRT-PCR). Small interfering RNA (siRNA) was then used to knock down the expression of HOTAIR in order to determine its role in RA FLSs. Cell viability was evaluated using the CCK-8 assay and flow cytometry. Cell invasion was analyzed by transwell chamber methodology. Bioinformatics analysis were performed to predict the possible competitive endogenous RNA (ceRNA) mechanisms via miRanda, PITA, RNAhybrid, as well as KEGG and Gene Ontology(GO) analysis.ResultsBoth microarray analysis and qRT-PCR showed the expressions of lncRNA HOTAIR were up-regulated in RA FLSs compared with healthy controls (HCs). Transfection of HOTAIR-siRNA significantly decreased the expression of lncRNA HOTAIR in RA FLSs. HOTAIR knockdown largely inhibited cell proliferation and invasion of RA FLSs. Furthermore, the bioinformatics analysis predicted that some of microRNAs and mRNAs may be the downstream molecules of lncRNA HOTAIR. Considering the mircoRNA expression profiles detected by microarrays and the results from qRT-PCR, we designated miR-138 and miR-17–5 p as potential ceRNAs which lncRNA HOTAIR could directly bind to. In addition, the expressions of miR-138 and miR-17–5 p were markedly downregulated in RA FLSs, whereas the knockdown of lncRNA HOTAIR upregulated the expressions compared with the negative control group (NC-siRNA).ConclusionsOur study illuminated that elevated lncRNA HOTAIR expression promoted the proliferation and invasion of RA FLSs. Meanwhile, it may function as a novel microRNAs sponging agent and regulate RA FLSs pathological behaviors via miR-138 or miR-17–5 p associated ceRNA network. In summary, the regulation of lncRNA HOTAIR may be a promising therapeutic strategy for RA in the future.AcknowledgementsThis work was supported by grants provided from Province Natural Science Fund of Guangdong, China (No.2014A030313080) and National Natural Science Foundation of China (No.81771750).Disclosure of InterestNone declared