Cloning and overexpression of an important functional gene ATP6V1F encoding a component of vacuolar ATPase from the Giant Panda (Ailuropoda melanoleuca)

ATP6V1F is a novel prognostic biomarker and potential immunotherapy target for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the deadliest malignancies worldwide, with late detection, ineffective treatment and poor overall survival. Immunotherapy, including immune checkpoint inhibitor (ICI) therapy, holds great potential for treatment of HCC. Although some patients respond well to ICIs, many fail to obtain a significant benefit. It is therefore of great interest to find appropriate markers to stratify patient responses to immunotherapy and to explore suitable targets for modulating the TME and immune cell infiltration. ATP6V1F encodes a constituent of vacuolar ATPase (V-ATPase). V-ATPase-mediated acidification of organelles is required for intracellular processes such as zymogen activation, receptor-mediated endocytosis, protein sorting and synaptic vesicle proton gradient generation. In this study, we confirmed for the first time that ATP6V1F is overexpressed in HCC and related to poor prognosis in these patients. We identified that overexpression of ATP6V1F is associated with infiltration of some immune cells and expression of several immune checkpoints. Furthermore, we explored the possible mechanisms of action of ATP6V1F. Finally, we conducted in vitro experiments, including wound healing, Transwell invasion, and apoptosis assays, to verify that ATP6V1F promotes development of HCC by promoting migration and invasion and inhibiting apoptosis of HCC cells. Our findings will contribute to providing precise immunotherapy to patients with HCC.

Molecular characterization of a gene POLR2H encoded an essential subunit for RNA polymerase II from the Giant Panda (Ailuropoda Melanoleuca)

The Giant Panda is an endangered and valuable gene pool in genetic, its important functional gene POLR2H encodes an essential shared peptide H of RNA polymerases. The genomic DNA and cDNA sequences were cloned successfully for the first time from the Giant Panda (Ailuropoda melanoleuca) adopting touchdown-PCR and reverse transcription polymerase chain reaction (RT-PCR), respectively. The length of the genomic sequence of the Giant Panda is 3,285 bp, including five exons and four introns. The cDNA fragment cloned is 509 bp in length, containing an open reading frame of 453 bp encoding 150 amino acids. Alignment analysis indicated that both the cDNA and its deduced amino acid sequence were highly conserved. Protein structure prediction showed that there was one protein kinase C phosphorylation site, four casein kinase II phosphorylation sites and one amidation site in the POLR2H protein, further shaping advanced protein structure. The cDNA cloned was expressed in Escherichia coli, which indicated that POLR2H fusion with the N-terminally His-tagged form brought about the accumulation of an expected 20.5 kDa polypeptide in line with the predicted protein. On the basis of what has already been achieved in this study, further deep-in research will be conducted, which has great value in theory and practical significance.