Viruses infecting marine picoplancton encode functional potassium ion channels

• Main Authors: Siotto, Fenja, Martin, Corinna, Rauh, Oliver, Van Etten, James L., Schroeder, Indra, Moroni, Anna, Thiel, Gerhard
• Format: Text
• Language: unknown
• Published: DigitalCommons@University of Nebraska - Lincoln 2014
• Subjects: K+ channel evolution; Kcv; Chlorella viruses; Algal viruses; Virus evolution; Genetics and Genomics; Life Sciences; Plant Pathology; Viruses; Antarc*; Antarctica
• Online Access: https://digitalcommons.unl.edu/vanetten/18; https://digitalcommons.unl.edu/context/vanetten/article/1018/viewcontent/Siotto_VIROLOGY_2014_Viruses_infecting_marine__DC_VERSION.pdf

Phycodnaviruses are dsDNA viruses, which infect algae. Their large genomes encode many gene products, like small K+ channels, with homologs in prokaryotes and eukaryotes. Screening for K+ channels revealed their abundance in viruses from fresh-water habitats. Recent sequencing of viruses from marine algae or from salt water in Antarctica revealed sequences with the predicted characteristics of K+ channels but with some unexpected features. Two genes encode either 78 or 79 amino acid proteins, which are the smallest known K+ channels. Also of interest is an unusual sequence in the canonical α-helixes in K+ channels. Structural prediction algorithms indicate that the new channels have the conserved α-helix folds but the algorithms failed to identify the expected transmembrane domains flanking the K+ channel pores. In spite of these unexpected properties electophysiological studies confirmed that the new proteins are functional K+ channels.