scholarly journals Ectopic expression of ecdysone oxidase impairs tissue degeneration in Bombyx mori

2015 ◽  
Vol 282 (1809) ◽  
pp. 20150513 ◽  
Author(s):  
Zhiqian Li ◽  
Lang You ◽  
Baosheng Zeng ◽  
Lin Ling ◽  
Jun Xu ◽  
...  
Keyword(s):  
Bombyx Mori ◽  
Ectopic Expression ◽  
Pupal Stage ◽  
Silk Gland ◽  
Signal Pathway ◽  
Rna Seq ◽  
Functional Studies ◽  
Tissue Degeneration ◽  
Transmission Electron ◽  
Autophagy Pathway

Metamorphosis in insects includes a series of programmed tissue histolysis and remolding processes that are controlled by two major classes of hormones, juvenile hormones and ecdysteroids. Precise pulses of ecdysteroids (the most active ecdysteroid is 20-hydroxyecdysone, 20E), are regulated by both biosynthesis and metabolism. In this study, we show that ecdysone oxidase (EO), a 20E inactivation enzyme, expresses predominantly in the midgut during the early pupal stage in the lepidopteran model insect, Bombyx mori . Depletion of BmEO using the transgenic CRISPR/Cas9 (clustered regularly interspaced short palindromic repeats/RNA-guided Cas9 nucleases) system extended the duration of the final instar larval stage. Ubiquitous transgenic overexpression of BmEO using the Gal4/UAS system induced lethality during the larval–pupal transition. When BmEO was specifically overexpressed in the middle silk gland (MSG), degeneration of MSG at the onset of metamorphosis was blocked. Transmission electron microscope and LysoTracker analyses showed that the autophagy pathway in MSG is inhibited by BmEO ectopic expression. Furthermore, RNA-seq analysis revealed that the genes involved in autophagic cell death and the mTOR signal pathway are affected by overexpression of BmEO . Taken together, BmEO functional studies reported here provide insights into ecdysone regulation of tissue degeneration during metamorphosis.

scholarly journals Comparison of Silks from Pseudoips prasinana and Bombyx mori Shows Molecular Convergence in Fibroin Heavy Chains but Large Differences in Other Silk Components

2021 ◽  
Vol 22 (15) ◽  
pp. 8246
Author(s):  
Michal Rindos ◽  
Lucie Kucerova ◽  
Lenka Rouhova ◽  
Hana Sehadova ◽  
Michal Sery ◽  
...  
Keyword(s):  
Bombyx Mori ◽  
Silk Gland ◽  
Amino Acid Sequences ◽  
Phylogenetic Distance ◽  
Rna Seq ◽  
Chain Molecules ◽  
Heavy Chains ◽  
Lepidopteran Larvae ◽  
Crystalline Domains

Many lepidopteran larvae produce silk feeding shelters and cocoons to protect themselves and the developing pupa. As caterpillars evolved, the quality of the silk, shape of the cocoon, and techniques in forming and leaving the cocoon underwent a number of changes. The silk of Pseudoips prasinana has previously been studied using X-ray analysis and classified in the same category as that of Bombyx mori, suggesting that silks of both species have similar properties despite their considerable phylogenetic distance. In the present study, we examined P. prasinana silk using ‘omics’ technology, including silk gland RNA sequencing (RNA-seq) and a mass spectrometry-based proteomic analysis of cocoon proteins. We found that although the central repetitive amino acid sequences encoding crystalline domains of fibroin heavy chain molecules are almost identical in both species, the resulting fibers exhibit quite different mechanical properties. Our results suggest that these differences are most probably due to the higher content of fibrohexamerin and fibrohexamerin-like molecules in P. prasinana silk. Furthermore, we show that whilst P. prasinana cocoons are predominantly made of silk similar to that of other Lepidoptera, they also contain a second, minor silk type, which is present only at the escape valve.

scholarly journals A Novel Adenosine Kinase from Bombyx mori: Enzymatic Activity, Structure, and Biological Function

2019 ◽  
Vol 20 (15) ◽  
pp. 3732 ◽  
Author(s):  
Kai Song ◽  
Yu Li ◽  
Huawei He ◽  
Lina Liu ◽  
Ping Zhao ◽  
...  
Keyword(s):  
Bombyx Mori ◽  
Gel Filtration ◽  
Pupal Stage ◽  
Adenosine Monophosphate ◽  
Silk Gland ◽  
Adenosine Kinase ◽  
Site Directed Mutagenesis ◽  
Activity Structure ◽  
Α Helix ◽  
And Function

Adenosine kinase (ADK) is the first enzyme in the adenosine remediation pathway that catalyzes adenosine phosphorylation into adenosine monophosphate, thus regulating adenosine homeostasis in cells. To obtain new insights into ADK from Bombyx mori (BmADK), we obtained recombinant BmADK, and analyzed its activity, structure, and function. Gel-filtration showed BmADK was a monomer with molecular weight of approximately 38 kDa. Circular dichroism spectra indicated BmADK had 36.8% α-helix and 29.9% β-strand structures, respectively. The structure of BmADK was stable in pH 5.0–11.0, and not affected under 30 °C. The melting temperature and the enthalpy and entropy changes in the thermal transition of BmADK were 46.51 ± 0.50 °C, 253.43 ± 0.20 KJ/mol, and 0.79 ± 0.01 KJ/(mol·K), respectively. Site-directed mutagenesis demonstrated G68, S201, E229, and D303 were key amino acids for BmADK structure and activity. In particular, S201A mutation significantly increased the α-helix content of BmADK and its activity. BmADK was located in the cytoplasm and highly expressed in the silk gland during the pre-pupal stage. RNA interference revealed the downregulation of BmADK decreased ATG-8, Caspase-9, Ec-R, E74A, and Br-C expression, indicating it was likely involved in 20E signaling, apoptosis, and autophagy to regulate silk gland degeneration and silkworm metamorphosis. Our study greatly expanded the knowledge on the activity, structure, and role of ADK.

Titanium nanoparticles influence the Akt/Tor signal pathway in the silkworm, Bombyx mori , silk gland

2018 ◽  
Vol 99 (1) ◽  
pp. e21470 ◽  
Author(s):  
Bin Xue ◽  
Fan-Chi Li ◽  
Jiang-Hai Tian ◽  
Jin-Xin Li ◽  
Xiao-Yu Cheng ◽  
...  
Keyword(s):  
Bombyx Mori ◽  
Silk Gland ◽  
Signal Pathway ◽  
Bombyx Mori Silk ◽  
Titanium Nanoparticles ◽  
Silkworm Bombyx Mori

scholarly journals Comparative mRNA and LncRNA Analysis of the Molecular Mechanisms Associated With Low Silk Production in Bombyx mori

2021 ◽  
Vol 11 ◽  
Author(s):  
Jinghua Ruan ◽  
Meiyu Wu ◽  
Xiaogang Ye ◽  
Shuo Zhao ◽  
Jianshe Liang ◽  
...  
Keyword(s):  
Bombyx Mori ◽  
Molecular Mechanisms ◽  
Excision Repair ◽  
Expression Profiles ◽  
Rna Degradation ◽  
Silk Gland ◽  
Rna Seq ◽  
Silk Production ◽  
Nucleotide Excision ◽  
Shock Proteins

Naked pupa sericin and Naked pupa are two mutant strains of Bombyx mori with extremely low or no fibroin production compared to the Qiufeng and Baiyu strains, both of which exhibit very high silk fibroin production. However, the molecular mechanisms by which long non-coding RNAs regulate fibroin synthesis need further study. In this study, we performed high-throughput RNA-seq to investigate lncRNA and mRNA expression profiles in the posterior silk gland of Qiufeng, Baiyu, Nd-sD, and Nd silkworms at the third day of the 5th instar. Our efforts yielded 26,767 novel lncRNAs and 6,009 novel mRNAs, the expression levels of silk protein genes and silk gland transcription factors were decreased in Qiufeng vs. Nd-sD and Qiufeng vs. Nd, while those of many genes related to autophagy, apoptosis, RNA degradation, ubiquitin-mediated proteolysis and heat shock proteins were increased. Moreover, the expression of a large number of genes responsible for protein synthesis and secretion was significantly decreased in Nd. GO and KEGG analysis results showed that nucleotide excision repair, mRNA surveillance pathways, amino acid degradation, protein digestion and absorption, ER-associated degradation and proteasome pathways were significantly enriched for the Qiufeng vs. Nd-sD and Qiufeng vs. Nd comparisons. In conclusion, our findings contribute to the lncRNA and mRNA database of Bombyx mori, and the identified differentially expressed mRNAs and lncRNAs help to reveal the molecular mechanisms of low silk production in Nd-sD and Nd, providing new insights for improvement of silk yield and elucidation of silk mechanical properties.

scholarly journals Molecular Basis of Urostyle Development: Genes and Gene Regulation Underlying an Evolutionary Novelty

2021 ◽  
Author(s):  
Gayani Senevirathne ◽  
Neil H. Shubin
Keyword(s):  
Vertebral Column ◽  
Developmental Stages ◽  
Stress Hormones ◽  
Ectopic Expression ◽  
Rna Seq ◽  
Evolutionary Novelty ◽  
T Box ◽  
Functional Studies ◽  
Laser Capture ◽  
Matrix Metallopeptidases

Evolutionary novelties entail the origin of morphologies that enable new functions. These features can arise through changes to gene function and regulation. One important novelty is the fused rod at the end of the vertebral column in anurans, the urostyle. This feature is composed of a coccyx and an ossifying hypochord, and both structures ossify during metamorphosis. We used Laser Capture Micro-dissection of these identified tissues and subjected them to RNA-seq and ATAC-seq analyses at three developmental stages in tadpoles of Xenopus tropicalis. These experiments reveal that the coccyx and hypochord have two different molecular signatures. ATAC-seq data reveals potential regulatory regions that are observed in proximity to candidate genes identified from RNA-seq. Neuronal (TUBB3) and muscle markers (MYH3) are upregulated in coccygeal tissues, whereas T-box genes (TBXT, TBXT.2), corticosteroid stress hormones (CRCH.1), and matrix metallopeptidases (MMP1, MMP8, MMP13) are upregulated in the hypochord. Even though an ossifying hypochord is only present in anurans, this ossification between the vertebral column and the notochord appears to resemble a congenital vertebral anomaly seen prenatally in humans, caused by an ectopic expression of the TBXT/TBXT.2 gene. This work opens the way to functional studies that help us better elucidate anuran bauplan evolution.

Role of Bm30kc6 gene in cell apoptosis and the silk gland degradation signaling pathway in Bombyx mori L.

2020 ◽  
Vol 105 (3) ◽  
Author(s):  
Ying Xiao ◽  
Lei‐lei Li ◽  
Asma Bibi ◽  
Ning Zhang ◽  
Ting Chen ◽  
...  
Keyword(s):  
Bombyx Mori ◽  
Signaling Pathway ◽  
Cell Apoptosis ◽  
Silk Gland ◽  
Bombyx Mori L

scholarly journals Single-cell RNA-seq reveals fibroblast heterogeneity and increased mesenchymal fibroblasts in human fibrotic skin diseases

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Cheng-Cheng Deng ◽  
Yong-Fei Hu ◽  
Ding-Heng Zhu ◽  
Qing Cheng ◽  
Jing-Jing Gu ◽  
...  
Keyword(s):  
Single Cell ◽  
Skin Disease ◽  
Skin Diseases ◽  
Rna Seq ◽  
Fibrotic Disease ◽  
Functional Studies ◽  
Fibrotic Diseases ◽  
Fibroblast Heterogeneity ◽  
Keloid Fibroblasts ◽  
Excessive Accumulation

AbstractFibrotic skin disease represents a major global healthcare burden, characterized by fibroblast hyperproliferation and excessive accumulation of extracellular matrix. Fibroblasts are found to be heterogeneous in multiple fibrotic diseases, but fibroblast heterogeneity in fibrotic skin diseases is not well characterized. In this study, we explore fibroblast heterogeneity in keloid, a paradigm of fibrotic skin diseases, by using single-cell RNA-seq. Our results indicate that keloid fibroblasts can be divided into 4 subpopulations: secretory-papillary, secretory-reticular, mesenchymal and pro-inflammatory. Interestingly, the percentage of mesenchymal fibroblast subpopulation is significantly increased in keloid compared to normal scar. Functional studies indicate that mesenchymal fibroblasts are crucial for collagen overexpression in keloid. Increased mesenchymal fibroblast subpopulation is also found in another fibrotic skin disease, scleroderma, suggesting this is a broad mechanism for skin fibrosis. These findings will help us better understand skin fibrotic pathogenesis, and provide potential targets for fibrotic disease therapies.

scholarly journals UXT chaperone prevents proteotoxicity by acting as an autophagy adaptor for p62-dependent aggrephagy

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Min Ji Yoon ◽  
Boyoon Choi ◽  
Eun Jin Kim ◽  
Jiyeon Ohk ◽  
Chansik Yang ◽  
...  
Keyword(s):  
Motor Neurons ◽  
Molecular Chaperones ◽  
Ectopic Expression ◽  
Protein Aggregates ◽  
Yeast Two Hybrid ◽  
Ubiquitinated Protein ◽  
Interacting Protein ◽  
Autophagy Pathway ◽  
Cooperative Relationship ◽  
Two Hybrid

Abstractp62/SQSTM1 is known to act as a key mediator in the selective autophagy of protein aggregates, or aggrephagy, by steering ubiquitinated protein aggregates towards the autophagy pathway. Here, we use a yeast two-hybrid screen to identify the prefoldin-like chaperone UXT as an interacting protein of p62. We show that UXT can bind to protein aggregates as well as the LB domain of p62, and, possibly by forming an oligomer, increase p62 clustering for its efficient targeting to protein aggregates, thereby promoting the formation of the p62 body and clearance of its cargo via autophagy. We also find that ectopic expression of human UXT delays SOD1(A4V)-induced degeneration of motor neurons in a Xenopus model system, and that specific disruption of the interaction between UXT and p62 suppresses UXT-mediated protection. Together, these results indicate that UXT functions as an autophagy adaptor of p62-dependent aggrephagy. Furthermore, our study illustrates a cooperative relationship between molecular chaperones and the aggrephagy machinery that efficiently removes misfolded protein aggregates.

Sage controls silk gland development by regulating Dfd in Bombyx mori

2021 ◽  
pp. 103568
Author(s):  
Sihan Hou ◽  
Cuicui Tao ◽  
Hongguo Yang ◽  
Tingcai Cheng ◽  
Chun Liu
Keyword(s):  
Bombyx Mori ◽  
Silk Gland ◽  
Gland Development
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