1. Academic Validation
  2. Molecular cloning and functional characterization of MYC transcription factor in pathogen-challenged Apostichopus japonicus

Molecular cloning and functional characterization of MYC transcription factor in pathogen-challenged Apostichopus japonicus

  • Dev Comp Immunol. 2020 Jan;102:103487. doi: 10.1016/j.dci.2019.103487.
Yi Zhang 1 Yina Shao 1 Zhimeng Lv 1 Weiwei Zhang 1 Xuelin Zhao 1 Ming Guo 1 Chenghua Li 2
Affiliations

Affiliations

  • 1 State Key Laboratory for Quality and Safety of Agro-products, Ningbo University, Ningbo, 315211, PR China.
  • 2 State Key Laboratory for Quality and Safety of Agro-products, Ningbo University, Ningbo, 315211, PR China; Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266071, PR China. Electronic address: [email protected].
Abstract

Myelocytomatosis viral oncogene (MYC), a transcription factor in the MYC family, plays vital roles in vertebrate innate immunity by regulating related immune gene expressions. In this study, we cloned and characterized an MYC gene from sea cucumber Apostichopus japonicus via RNA-seq and RACE approaches (designated as AjMYC). A 2074 bp fragment representing the full-length cDNA of AjMYC was obtained. This gene includes an open reading frame (ORF) of 1296 bp encoding a polypeptide of 432 amino acid residues with the molecular weight of 48.85 kDa and theoretical pI of 7.22. SMART analysis indicated that AjMYC shares an MYC common HLH motif (354-406 aa) at the C-terminal. Spatial expression analysis revealed that AjMYC is constitutively expressed in all detected tissues with peak expression in the tentacle. Vibrio splendidus-challenged sea cucumber could significantly boost the expression of AjMYC transcripts by a 5.58-fold increase in the first stage. Similarly, 2.75- and 3.23-fold increases were detected in LPS-exposed coelomocytes at 1 and 24 h, respectively. In this condition, coelomocyte apoptotic rate increased from 11.98% to 56.23% at 1 h and to 59.08% at 24 h. MYC inhibitor treatment could not only inhibit the expression of AjMYC and Ajcaspase3, but also depress the coelomocyte Apoptosis. Furthermore, AjMYC overexpression in EPC cells for 24 h also promoted the cell Apoptosis rate from 21.31% to 45.85%. Collectively, all these results suggested that AjMYC is an important immune factor in coelomocyte Apoptosis toward pathogen-challenged sea cucumber.

Keywords

Apoptosis; Apostichopus japonicus; EPC cell; MYC inhibitor; Myelocytomatosis viral oncogene.

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