Molecular insights and immune responses of big belly seahorse syndecan-2 (CD362): Involvement of ectodomain in regulating cell survival, proliferation, and wound healing

Identification, molecular characterization, expression analysis and wound-healing ability of multifunctional calreticulin from big-belly seahorse Hippocampus abdominalis

Calreticulin (CRT) is a multifunctional ubiquitous protein that is widely presented in all cells in eukaryotes except erythrocytes. CRT is well known for diverse cellular functions such as endoplasmic reticulum (ER)-specialized protein quality control during protein synthesis and folding, in-vivo Ca²⁺ homeostasis, antigen presentation, phagocytosis, wound-healing, proliferation, adhesion, and migration of cells. In the current study, we identified CRT from Hippocampus abdominalis (HaCRT) and analyzed expression profiles and functional properties. The cDNA sequence of HaCRT was identified with an open reading frame of 1226 bp. The molecular weight of HaCRT was estimated as 49 kDa. The in-silico study revealed conserved sequence arrangements such as two CRT signature motifs (5'-KHEQSIDCGGGYVKVF-3' and 5'-LMFGPDICG-3'), triplicate repeats (5'-IKDPEAKKPEDWD-3', 5'-IPDPDDTKPEDWD-3', 5'-IPDPDAKKPDDWD-3'), signal peptide and an ER-targeting 5'-KDEL-3' sequence of HaCRT. Close sequence similarity of HaCRT was observed with Hippocampus comes from phylogenetic analysis and pairwise sequence comparison. From quantitative polymerase chain reaction (qPCR) results, HaCRT was ubiquitously distributed in all tested tissues and expression levels of HaCRT were significantly modulated in blood, liver and gill tissues after stimulation with Streptococcus iniae, Edwardsiella tarda, polyinosinic:polycytidylic acid, and lipopolysaccharides. Bacterial- and pathogen-associated molecular patterns-binding activities were observed with recombinant HaCRT (rHaCRT). The treatment of murine macrophages with rHaCRT induced the expression of immune genes, such as tumor necrosis factor-α (TNF-α), interleukin 6 (IL-6), inducible nitric oxide synthase (iNOS), and interleukin-1β (IL-1β). Furthermore, rHaCRT exhibited wound-healing ability. Based on the results from the above study, we suggest that HaCRT play an indispensable role in the immunity of big-belly seahorses by recognition and elimination of pathogens as well as the tissue repairing process.

Identification of a Recurrence Signature and Validation of Cell Infiltration Level of Thyroid Cancer Microenvironment

Though many patients with thyroid cancer may be indolent, there are still about 50% lymph node metastases and 20% the recurrence rates. There is still no ideal method to predict its relapse. In this study, we analyzed the gene transcriptome profiles of eight Gene Expression Omnibus (GEO), and next screened 77 commonly differential expressed genes. Next, Least Absolute Shrinkage and Selection Operator (LASSO) regression model was performed and seven genes (i.e., FN1, PKIA, TMEM47, FXYD6, SDC2, CD44, and GGCT) were then identified, which is highly associated with recurrence data from the Cancer Genome Atlas (TCGA) database. These patients were then divided into low and high-risk groups with specific risk-score formula. Univariate and multivariate Cox regression further revealed that the 7-mRNA signature plays a functional causative role independent of clinicopathological characteristics. The 7-mRNA-signature integrated nomogram showed better discrimination, and decision curve analysis demonstrated that it is clinically useful. Besides, patient with lower risk score shows a relatively lower level of activated dendritic cells (DCs), resting DCs, regulatory T cells and γδT cells, and process of DCs apoptotic. In conclusion, our present immune-related classifier could produce a potential tool for predicting early-relapse.