Comparative RNA-sequencing analysis of mthl1 functions and signal transductions in Tribolium castaneum

Mulberry-derived miR168a downregulates BmMthl1 to promote physical development and fecundity in silkworms

Plant-derived miRNAs and their interactions with host organisms are considered important factors in regulating host physiological processes. In this study, we investigated the interaction between the silkworm, an oligophagous insect, and its primary food source, mulberry, to determine whether mulberry-derived miRNAs can penetrate silkworm cells and regulate their functions. Our results demonstrated that miR168a from mulberry leaves enters the silkworm hemolymph and binds to the silkworm Argonaute1 BmAGO1, which is transported via vesicles secreted by silkworm cells to exert its regulatory functions. In vivo and in vitro functional studies revealed that miR168a targets the mRNA of silkworm G protein-coupled receptor, BmMthl1, thereby inhibiting its expression and activating the JNK-FoxO pathway. This activation reduces oxidative stress responses, prolongs the lifespan of silkworms, and improves their reproductive capacity. These findings highlight the challenges of replacing mulberry leaves with alternative protein sources and provide a foundation for developing silkworm germplasms suitable for factory rearing.

Characterization and expression profiling of G protein-coupled receptors (GPCRs) in Spodoptera litura (Lepidoptera: Noctuidae)

Spodoptera litura is a highly destructive omnivorous pest, and they caused serious damage to various crops. G protein-coupled receptors (GPCRs) mediate dozens of physiological processes including reproduction, development, life span and behaviors, but the information of these receptors has been lacking in S. litura. Here, we methodically identified 122 GPCRs in S. litura and made an assay of their expression patterns in different tissues. Comparing the identified GPCRs with homologous genes of other insects, it is obvious that the subfamily A2 (biogenic amine receptors) and the subfamily A3 (neuropeptide and protein hormone receptors) of S. litura have expanded to a certain extent, which may be related to the omnivorous nature and drought environment resistance of S. litura. Besides, the large Methuselah (Mth)/Methuselah-like (Mthl) subfamily of S. litura may be involved in many physiological functions such as longevity and stress response. Apart from duplicate receptors, the loss of parathyroid hormone receptor (PTHR) and the bride of sevenless (Boss) receptor in the lepidopteran insects may imply a new pattern of wing formation and energy metabolism in lepidopteran insects. In addition, the high expression level of GPCRs in different tissues reflects the functional diversity of GPCRs regulating. Systemic identification and initial characterization of GPCRs in S. litura provide a basis for further studies to reveal the functions of these receptors in regulating physiology and behavior.

G protein-coupled receptors that influence lifespan of human and animal models

Humanity has always sought to live longer and for this, multiple strategies have been tried with varying results. In this sense, G protein-coupled receptors (GPCRs) may be a good option to try to prolong our life while maintaining good health since they have a substantial participation in a wide variety of processes of human pathophysiology and are one of the main therapeutic targets. In this way, we present the analysis of a series of GPCRs whose activity has been shown to affect the lifespan of animal and human models, and in which we put a special interest in describing the molecular mechanisms involved. Our compilation of data revealed that the mechanisms most involved in the role of GPCRs in lifespan are those that mimic dietary restriction, those related to insulin signaling and the AMPK and TOR pathways, and those that alter oxidative homeostasis and severe and/or chronic inflammation. We also discuss the possibility of using agonist or antagonist drugs, depending on the beneficial or harmful effects of each GPCR, in order to prolong people's lifespan and healthspan.

Physiological functions of a methuselah-like G protein coupled receptor in Lymantria dispar Linnaeus

Insect G protein coupled receptors (GPCRs) have been identified as a highly attractive target for new generation insecticides discovery due to their critical physiological functions. However, few insect GPCRs have been functionally characterized. Here, we cloned the full length of a methuselah-like GPCR gene (Ldmthl1) from the Asian gypsy moth, Lymantria dispar. We then characterized the secondary and tertiary structures of Ldmthl1. We also predicted the global structure of this insect GPCR protein which is composed of three major domains. RNA interference of Ldmthl1 resulted in a reduction of gypsy moths' resistance to deltamethrin and suppressed expression of downstream stress-associated genes, such as P450s, glutathione S transferases, and heat shock proteins. The function of Ldmthl1 was further investigated using transgenic lines of Drosophila melanogaster. Drosophila with overexpression of Ldmthl1 showed significantly longer lifespan than control flies. Taken together, our studies revealed that the physiological functions of Ldmthl1 in L. dispar are associated with longevity and resistance to insecticide stresses. Potentially, Ldmthl1 can be used as a target for new insecticide discovery in order to manage this notorious forest pest.

CYP4BN6 and CYP6BQ11 mediate insecticide susceptibility and their expression is regulated by Latrophilin in Tribolium castaneum

BACKGROUND

Many insect cytochrome P450 proteins (CYPs) are involved in the metabolic detoxification of exogenous compounds such as plant toxins and insecticides. Tribolium castaneum, the red flour beetle, is a major agricultural pest that damages stored grains and cereal products. With the completion of the sequencing of its genome, two T. castaneum species-specific CYP genes, CYP4BN6, and CYP6BQ11, were identified. However, it is unknown whether the functions of most CYPs are shared by TcCYP4BN6 and TcCYP6BQ11, and the upstream regulatory mechanism of these two CYPs remains elusive.

RESULTS

QRT-PCR analysis indicated that TcCYP4BN6 and TcCYP6BQ11 were both most highly expressed at the late pupal stage and were mainly observed in the head and gut, respectively, of adults. Moreover, the transcripts of these two CYPs were significantly induced by dichlorvos and carbofuran, and RNA interference (RNAi) targeting of each of them enhanced the susceptibility of beetles to these two insecticides. Intriguingly, knockdown of the latrophilin (lph) gene, which has been reported to be related to the insecticide susceptibility, reduced the expression of TcCYP4BN6 and TcCYP6BQ11 after insecticide treatment, suggesting that these two CYP genes are regulated by lph to participate in insecticide susceptibility in T. castaneum.

CONCLUSION

These results shed new light on the function and mechanism of CYP genes associated with insecticide susceptibility and could facilitate research on appropriate and sustainable pest control management. © 2019 Society of Chemical Industry.

Upregulation of FOXP4 in breast cancer promotes migration and invasion through facilitating EMT

Background

Family of forkhead box transcription factors has been found to play key roles in multiple types of cancer.

Materials and methods

Our study is to decipher the effects of FOXP4 in human breast cancer (BC). Quantitative real-time polymerase chain reaction and Western blot analyses were performed to determine the mRNA and protein expressions of FOXP4 in BC tissue samples and cell lines. The gain and loss of function assay were used to explore the detailed roles of FOXP4 in breast cell lines, including MDA-MB-231 and MCF-7 cells. Its effect on BC growth, migration, and invasion were evaluated by colony formation assay, CCK-8 assay, wound-healing assay, and transwell invasion assay, respectively.

Results

Our findings revealed that FOXP4 promotes cell proliferation, migration, as well as invasion of BC cells. Furthermore, FOXP4 also facilitates epithelial-mesenchymal transition. ChIP, qChIP assay, and dual luciferase reporter assay were used to examine whether Snail is a downstream target of FOXP4. Moreover, overexpression of Snail could partially rescue the effects of FOXP4 inhibition on cancer cell migration and invasion.

Conclusion

Our findings revealed that FOXP4 is a critical regulator in BC.

TRPS1 Suppresses Breast Cancer Epithelial-mesenchymal Transition Program as a Negative Regulator of SUZ12

Breast cancer (BC) is among the most common malignant diseases and metastasis is the handcuff of treatment. Cancer metastasis is a multistep process associated with the epithelial-mesenchymal transition (EMT) program. Several studies have demonstrated that transcriptional repressor GATA binding 1 (TRPS1) played important roles in development and progression of primary BC. In this study we sought to identify the mechanisms responsible for this function of TRPS1 in the continuum of the metastatic cascade. Here we described that TRPS1 was significantly associated with BC metastasis using public assessable datasets. Clinically, loss of TRPS1 expression in BC was related to higher histological grade. In vitro functional study and bioinformatics analysis revealed that TRPS1 inhibited cell migration and EMT in BC. Importantly, we identified SUZ12 as a novel target of TRPS1 related to EMT program. ChIP assay demonstrated TRPS1 directly inhibited SUZ12 transcription by binding to the SUZ12 promoter. Loss of TRPS1 resulted in increased SUZ12 binding and H3K27 tri-methylation at the CDH1 promoter and repression of E-cadherin. In all, our data indicated that TRPS1 maintained the expression of E-cadherin by inhibiting SUZ12, which might provide novel insight into how loss of TRPS1 contributed to BC progression.

Comparative RNA-sequencing analysis of ER-based HSP90 functions and signal pathways in Tribolium castaneum

Tribolium castaneum, the red flour beetle, is a major agriculture pest that damages stored grains and cereal products. Heat-shock protein 90 of T. castaneum (Tchsp90) has been reported to play pivotal roles in heat stress response, development, reproduction, and life span. However, the signaling pathway of Tchsp90 remains unclear. Thus, the global transcriptome profiles between RNA interference (RNAi)-treated insects (ds-Tchsp90) and control insects of T. castaneum were investigated and compared by RNA sequencing. In all, we obtained 14,145,451 sequence reads, which assembled into 13,243 genes. Among these genes, 461 differentially expressed genes (DEGs) were identified between the ds-Tchsp90 and control samples. These DEGs were classified into 44 gene ontology (GO) functional groups, including the cellular process, the response to stimulus, the immune system process, the development process, and reproduction. Interestingly, knocking down the expression of Tchsp90 suppressed both the DNA replication and cell division signaling pathways, which most likely modulated the effects of Tchsp90 on development, reproduction, and life span. Moreover, the DEGs encoding AnnexinB9, frizzled-4, sno, Fem1B, TSL, and CSW might be related to the regulation of the development and reproduction of ds-Tchsp90 insects. The DEGs including TLR6, PGRP2, defensin1, and defensin2 were involved in heat stress and immune response simultaneously, which suggested that cross talk might exist between immunity and stress response. Additionally, RNAi of Tchsp90 altered large-scale serine protease (sp) gene expression patterns and amplified the SP signaling pathway to regulate the development and reproduction as well as the stress response and innate immunity in T. castaneum. All these results shed new light onto the regulatory mechanism of Tchsp90 involved in insect physiology and could further facilitate research into appropriate and sustainable pest control management.

Hepatopancreas transcriptome analysis of Chinese mitten crab (Eriocheir sinensis) with white hepatopancreas syndrome

White hepatopancreas is a syndrome that has recently emerged in aquaculture of Chinese mitten crab (Eriocheir sinensis). High lethality of the disease caused large economic loss, which drew considerable attention of fish farmers and scientific researchers. In this study, hepatopancreas reference transcriptome was de novo assembled and differential expression analysis was conducted between white hepatopancreas and normal (yellow) hepatopancreas of E. sinensis. A total of 90,687 transcripts were assembled, and 27,387 were annotated. Transcriptomic comparison revealed 69 differentially expressed genes between individuals featuring white hepatopancreas and yellow hepatopancreas. Genes associated with immune response and cell death, include thioredoxin-related transmembrane protein 1, hemocytin, methuselah-like 1, and E3 ubiquitin-protein ligase, and they were up-regulated, whereas titin and 5-formyltetrahydrofolate cyclo-ligase, which are genes related to cell proliferation, were down-regulated in E. sinensis with white hepatopancreas syndrome. Our study provides novel insights into genetic causes of formation and novel gene markers for detection of white hepatopancreas syndrome in aquaculture of E. sinensis.

Gene Ages, Nomenclatures, and Functional Diversification of the Methuselah/Methuselah-Like GPCR Family in Drosophila and Tribolium

Affecting lifespan regulation and oxidative stress resistance, the G-protein coupled receptor (GPCR) gene methuselah (mth) plays important roles in the life history of Drosophila melanogaster. Substantial progress has been made in elucidating the molecular pathways by which mth affects these traits, yet conflicting ideas exist as to how old these genetic interactions are as well as how old the mth gene itself is. Root to these issues is the complex gene family history of the Mth/Mthl GPCR family, which experienced independent expansions in a variety of animal clades, leading to at least six subfamilies in insects. Within insects, drosophilid flies stand out by possessing up to three times more Mth/Mthl receptors due to the expansion of a single subfamily, the mth superclade subfamily, which contains an even younger subfamily introduced here as the melanogaster subgroup subfamily. As a result, most of the 16 Mth/Mthl receptors of D. melanogaster are characterized by n:1 orthology relationships to singleton mth superclade homologs in nondrosophilid species. This challenge is exacerbated by the inconsistent naming of Mth/Mthl orthologs across species. To consolidate this situation, we review established ortholog relationships among insect Mth/Mthl receptors, clarify the gene nomenclatures in two important satellite model species, the fruit fly relative D. virilis and the red flour beetle Tribolium castaneum, and discuss the genetic and functional evolution of the D. melanogaster Mth GPCR.

Methuselah/Methuselah-like G protein-coupled receptors constitute an ancient metazoan gene family

Inconsistent conclusions have been drawn regarding the phylogenetic age of the Methuselah/Methuselah-like (Mth/Mthl) gene family of G protein-coupled receptors, the founding member of which regulates development and lifespan in Drosophila. Here we report the results from a targeted homolog search of 39 holozoan genomes and phylogenetic analysis of the conserved seven transmembrane domain. Our findings reveal that the Mth/Mthl gene family is ancient, has experienced numerous extinction and expansion events during metazoan evolution, and acquired the current definition of the Methuselah ectodomain during its exceptional expansion in arthropods. In addition, our findings identify Mthl1, Mthl5, Mthl14, and Mthl15 as the oldest Mth/Mthl gene family paralogs in Drosophila. Future studies of these genes have the potential to define ancestral functions of the Mth/Mthl gene family.

Dusky-like is required for epidermal pigmentation and metamorphosis in Tribolium castaneum

Dusky-like (Dyl) is associated with the morphogenesis of embryonic denticle, adult sensory bristle and wing hair in Drosophila melanogaster. And whether Dyl involved in insect post-embryonic development and its signal transduction are poorly understood. Here, phylogenetic analysis revealed that dyl displayed one-to-one orthologous relationship among insects. In Tribolium castaneum, dyl is abundantly expressed at the late embryonic stage. Tissue-specific expression analysis at the late adult stage illustrated high expression of dyl in the fat body and ovary. Knockdown of dyl resulted in the defects in larval epidermal pigmentation and completely blocked the transitions from larval to pupal and pupal to adult stages of T. castaneum. We further discovered that dyl RNAi phenotypes were phenocopied by blimp-1 or shavenbaby (svb) silencing, and dyl was positively regulated by blimp-1 through svb in T. castaneum. These results suggest that Dyl functions downstream of Blimp-1 through Svb for larval epidermal pigmentation and metamorphosis. Moreover, ftz-f1 was down-regulated after RNA interference (RNAi) suppressing any of those three genes, indicating that Ftz-f1 works downstream of Dyl to mediate the effects of Blimp-1, Svb and Dyl on metamorphosis in T. castaneum. This study provides valuable insights into functions and signaling pathway of insect Dyl.