Comparative transcriptome analysis of wing discs from Bombyx mori and Bombyx mandarina

Feng Yongjie,Kumar Dhiraj,Hu Xiaolong,Zhang Yiling,Zhu Min,Xue Renyu,Cao Guangli,Gong Chengliang 한국응용곤충학회 2020 Journal of Asia-Pacific Entomology Vol.23 No.2

The insect wing is developed from the wing imaginal disc which is designed from the embryonic ectoderm. To get insight into gene expression profiles in wing discs of Bombyx mori during metamorphosis, we compared the gene expression in the wing between B. mori and B. mandarina moth through RNA-seq. Out of total valid reads identified from the 5th day of 5th instar larvae of silkworm (L5), 7th day of pupae (P7), 1st day of moth (M1) and 1st day of wild silkworm moth (WM1), 20,092,004, 29,251,647, 24,654,695 and 19,753,089 reads were mapped to the mRNA reference sequences of silkworm, respectively. 9229, 7048, 9268 and 6701 differentially expressed genes (DEGs) were respectively recorded in P7 vs L5, M1 vs P7, M1 vs L5 and WM1 vs M1. Further, the peroxisome, ribosome, endocytosis and oxidative phosphorylation pathways were significantly regulated in the metamorphosis of the silkworm. Our study identified 16 orthologous genes with a positive selection from M1, which might be subjected to artificial selection in the domestication of B. mori and would play vital roles in the flight of B. mandarina.

Study of gut bacterial diversity of Bombyx mandarina and Bombyx mori through 16S rRNA gene sequencing

Dhiraj Kumar,Zhenli Sun,Guangli Cao,Renyu Xue,Xiaolong Hu,Chengliang Gong 한국응용곤충학회 2019 Journal of Asia-Pacific Entomology Vol.22 No.2

The wild silkworm B. mandarina is living in the natural environment has a strong stress resistance and adaptability after harsh natural selection. The indoor rearing or domestication of the wild silkworm under artificial custody for long period deteriorates stress resistance and ecological adaptability. Therefore, we aimed to investigate the effects of artificial domestication and evolutionary pressure on the gut bacterial diversity of B. mandarina and B. mori. The intestinal content of 6th day of fifth instar B. mandarina and B. mori larvae were analyzed by sequencing of the 16S rRNA gene through Illumina miseq sequencing technology. The outcome of the study revealed that abundance of predominant bacteria of phylum Firmicutes were respectively 81.40% and 81.85% in the late fifth instar silkworm larvae (6th day) of B. mandarina and B. mori. In Firmicutes, abundance of predominant bacterial genus Enterococcus in B. mandarina (69.73%) was comparatively higher than B. mori (48.99%). The genus Advenella belongs to phylum Proteobacteria was recorded only in B. mandarina (11.54%). The abundance of Unclassified_Peptostreptococcaceae, Methanobrevibacter, Ignatzschineria, Petrimonas and Proteiniphilum in B. mandarina were between 0.12 and 0.17%, nevertheless, these bacterial genera were not detected in B. mori. The abundance of genera Lactococcus, Bacillus and Pseudomonas in B. mori (17.73%, 5.02%, and 1.61%) were remarkably higher than B. mandarina (0.15%, 0.54% and 0.45%). These results indicated that substantial difference was observed between the intestinal bacteria of B. mori and B. mandarina population, and structure of the intestinal bacteria could be affected by the artificial domestication and evolutionary pressure.

Transient propagation of BmLV and dysregulation of gene expression in nontarget cells following BmLV infection

Feng Yongjie,Zhang Xing,Kumar Dhiraj,Kuang Sulan,Liu Bo,Hu Xiaolong,Zhu Min,Liang Zi,Cao Guangli,Xue Renyu,Gong Chengliang 한국응용곤충학회 2021 Journal of Asia-Pacific Entomology Vol.24 No.3

Bombyx mori latent virus (BmLV), a novel positive-strand RNA virus was first identified in the B. mori cultured BmN cell line. Whether the infectivity of BmLV to silkworm larvae and non-silkworm cells is connected with dysregulation of gene expression are not well understood. A complete sequence of BmLV genomic RNA was identified and revealed that a fragment with 495 nt in length was deleted from the RNA-dependent RNA poly merase (RdRp) gene in some BmLV genomic RNAs. Studies on the infectivity of BmLV to nontarget cells showed that BmLV can infect silkworm larvae, Spodoptera frugiperda Sf-9 and H1299 lung cancer cells with transient propagation. The dysregulation of gene expression of Sf-9 cells followed by BmLV infection was analyzed. Out of 743 differentially expressed genes (DEGs), 300 were upregulated and 443 were downregulated. Gene Ontology (GO) analysis indicated the DEGs were enriched into oxidoreductase activity for CH-NH 2 group donors, gluta mate biosynthetic process, response to stress and proteasome core complex. KEGG enrichment analysis showed that DEGs were mainly enriched into sulfur metabolism, RNA degradation, proteasome, pentose and glucuronate interconversions. Undesirable nutrients and temperature factors contributed to the propagation of BmLV in Sf-9 cells. Additionally, the Imd and RNAi pathways were activated by BmLV infection without stimulating Toll and JAK-STAT pathways. Therefore, it is suggested that BmLV is originated from plants, which can enter nontarget cells with transient propagation. The transient infection of BmLV may not only be regulated by Imd and RNAi immune pathways but also mediated by dysregulation of gene expression.

Cell proliferation can be modulated by receptor tyrosine kinase-like orphan receptor 2 in the silkworm, Bombyx mori

Yongjie Feng,Wei Liu,Dhiraj Kumar,Min Zhu,Renyu Xue,Guangli Cao,Xiaolong Hu,Chengliang Gong 한국응용곤충학회 2023 Journal of Asia-Pacific Entomology Vol.26 No.4

The receptor tyrosine kinase-like orphan receptor 2 (Ror2) is involved in the Wnt/β-catenin signaling pathway which regulates cell proliferation, polarity, differentiation, migration, metabolism and survival. However, the function of Ror2 in the silkworm Bombyx mori is still undisclosed. In the present investigation, we have made an effort to clone the silkworm Ror2 gene (BmRor2). The sequence analysis showed that the open reading frame (ORF) was 1914 bp in size and encoded a protein with the conserved domains of Ror2 protein. The qRT-PCR results indicated that the BmRor2 gene expression level was the highest in the head among all identified tis sues on 3rd day of the fifth instar larvae. In the gonads of the different development stages, the BmRor2 gene expression level was highest on the 4th day of the fourth instar larvae. The immunofluorescence assay indicated that the BmRor2 protein was located at the cytomembrane. The effects of BmRor2 protein on the expression levels of genes related to TGF-β, Hippo, JAK-STAT and Notch signaling pathways were investigated by qRT-PCR. The expression levels of crumbs (crb), warts (wts), α-catenin (cat), four-jointed (fj), decapentaplegic (dpp), kibra ortholog (kibra), serrate (serr) and c-myc (myc) genes were down-regulated, whereas, suppressor of cytokine signaling 2 (socs 2) gene expression was up-regulated in the cultured BmN cells after the BmRor2 expression level was up-regulated. Further, cell proliferation was demoted and the size of cells was decreased when BmRor2 expression level was elevated. Our current finding recommended that BmRo2 can regulate TGF- β, Hippo, JAKSTAT, and Notch signaling pathways, and affect cell proliferation and size.

Fatty Acid-Binding Protein 4 in Patients with and without Diabetic Retinopathy

Ping Huang,Xiaoqin Zhao,Yi Sun,Xinlei Wang,Rong Ouyang,Yanqiu Jiang,Xiaoquan Zhang,Renyue Hu,Zhuqi Tang,Yunjuan Gu 대한당뇨병학회 2022 Diabetes and Metabolism Journal Vol.46 No.4

Background: Fatty acid-binding protein 4 (FABP4) has been demonstrated to be a predictor of early diabetic nephropathy. However, little is known about the relationship between FABP4 and diabetic retinopathy (DR). This study explored the value of FABP4 as a biomarker of DR in patients with type 2 diabetes mellitus (T2DM).Methods: A total of 238 subjects were enrolled, including 20 healthy controls and 218 T2DM patients. Serum FABP4 levels were measured using a sandwich enzyme-linked immunosorbent assay. The grade of DR was determined using fundus fluorescence angiography. Based on the international classification of DR, all T2DM patients were classified into the following three subgroups: non-DR group, non-proliferative diabetic retinopathy (NPDR) group, and proliferative diabetic retinopathy (PDR) group. Multivariate logistic regression analyses were employed to assess the correlation between FABP4 levels and DR severity.Results: FABP4 correlated positively with DR severity (<i>r</i>=0.225, <i>P</i>=0.001). Receiver operating characteristic curve analysis was used to assess the diagnostic potential of FABP4 in identifying DR, with an area under the curve of 0.624 (37% sensitivity, 83.6% specificity) and an optimum cut-off value of 76.4 μg/L. Multivariate logistic regression model including FABP4 as a categorized binary variable using the cut-off value of 76.4 μg/L showed that the concentration of FABP4 above the cut-off value increased the risk of NPDR (odds ratio [OR], 3.231; 95% confidence interval [CI], 1.574 to 6.632; <i>P</i>=0.001) and PDR (OR, 3.689; 95% CI, 1.306 to 10.424; <i>P</i>=0.014).Conclusion: FABP4 may be used as a serum biomarker for the diagnosis of DR.