biostudies-literatureUnknown10(1)Guan WNatural Sciences and Engineering Research Council of CanadaHeart and Stroke Foundation of CanadaInvertebrate LCa_V3 shares the quintessential features of vertebrate Ca_V3 T-type channels, with a low threshold of channel activation, rapid activation and inactivation kinetics and slow deactivation kinetics compared to other known Ca²⁺ channels, the Ca_V1 and Ca_V2 channels. Unlike the vertebrates though, Ca_V3 T-type channels in non-cnidarian invertebrates possess an alternative exon 12 spanning the D2L5 extracellular loop, which alters the invertebrate LCa_V3 channel into a higher Na⁺ and lower Ca²⁺ current passing channel, more resembling a classical Na_V1 Na⁺ channel. Cnidarian Ca_V3 T-type channels can possess genes with alternative cysteine-rich, D4L6 extraceScientific reports12404https://www.ebi.ac.uk/biostudies/studies/S-EPMC7382465biostudies-literatureUnique cysteine-enriched, D2L5 and D4L6 extracellular loops in Ca_V3 T-type channels alter the passage and block of monovalent and divalent ions.PMC7382465Fux JStephens RFGuan WMehta AMourad OSpafford JDfalseUnique cysteine-enriched, D2L5 and D4L6 extracellular loops in Ca_V3 T-type channels alter the passage and block of monovalent and divalent ions.Invertebrate LCa_V3 shares the quintessential features of vertebrate Ca_V3 T-type channels, with a low threshold of channel activation, rapid activation and inactivation kinetics and slow deactivation kinetics compared to other known Ca²⁺ channels, the Ca_V1 and Ca_V2 channels. Unlike the vertebrates though, Ca_V3 T-type channels in non-cnidarian invertebrates possess an alternative exon 12 spanning the D2L5 extracellular loop, which alters the invertebrate LCa_V3 channel into a higher Na⁺ and lower Ca²⁺ current passing channel, more resembling a classical Na_V1 Na⁺ channel. Cnidarian Ca_V3 T-type channels can possess genes with alternative cysteine-rich, D4L6 extrace2020-01-01T00:00:00Z2020 Jul2026-05-03T00:07:08.214Z2020-11-08T09:38:31ZS-EPMC73824653271008810.1038/s41598-020-69197-3