{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,2]],"date-time":"2025-11-02T16:40:40Z","timestamp":1762101640606},"reference-count":0,"publisher":"Wiley","issue":"1","license":[{"start":{"date-parts":[[1993,2,1]],"date-time":"1993-02-01T00:00:00Z","timestamp":728524800000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/onlinelibrary.wiley.com\/termsAndConditions#vor"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["The Journal of Physiology"],"published-print":{"date-parts":[[1993,2]]},"abstract":"<jats:p>1. Ras\u2010transformed fibroblasts have a whole\u2010cell Ca(2+)\u2010activated K+ current which is either absent or unavailable for activation in their non\u2010transformed counterparts. To better understand the physiological significance of this K+ current the single channel basis for the current was characterized in ras\u2010transformed cells. 2. More than 90% of inside\u2010out patches from ras\u2010transformed balb 3T3 cells had a channel type which was Ca(2+)\u2010activated (threshold &lt; 0.2 microM internal Ca2+), K(+)\u2010selective (permeability ratio PNa:PK &lt; 0.02), and inwardly rectifying in symmetric 150 mM KCl solutions (conductances at \u201060 and 60 mV of 33 +\/\u2010 1 and 17 +\/\u2010 1 pS respectively). Channel opening probability increased 25\u201050% between \u201060 and 60 mV due to an increase in the frequency of opening. Single K+ channels in outside\u2010out patches were blocked by externally applied 10 mM TEA or 100 nM charybdotoxin, as were whole\u2010cell Ca(2+)\u2010activated K+ currents. The properties of this class of K+ channel are sufficient to account for the whole\u2010cell Ca(2+)\u2010activated current in ras\u2010transformed cells. 3. Inside\u2010out patches from C3H10T1\/2 and NIH 3T3 fibroblasts transformed by the H\u2010ras oncogene had Ca(2+)\u2010activated K+ channels identical to those observed in K\u2010ras\u2010transformed balb 3T3 cells. 4. As predicted from whole\u2010cell experiments Ca(2+)\u2010activated K+ channels were not observed in inside\u2010out patches from non\u2010transformed balb 3T3 cells. The purpose of the excised patch recordings was, instead, to rule out potential technical complications with the whole\u2010cell experiments. For instance A23187, which evoked whole\u2010cell K+ currents in transformed cells, may not have elevated Ca2+ sufficiently to allow K+ channel activation in non\u2010transformed cells. Another possibility was that trypsin pretreatment used to round\u2010up cells for whole\u2010cell recording may have preferentially disabled channels in non\u2010transformed cells. The first problem was addressed by exposing patches from non\u2010transformed cells to 100\u20101000 microM Ca2+. Excised patches were also taken from non\u2010transformed cells which had not been exposed to trypsin. K+ channel activity was not observed under either condition. 5. Patches from both ras\u2010transformed and non\u2010transformed cells had a type of non\u2010specific cation channel which was activated at internal Ca2+ concentrations &gt; or = 100 microM. This channel was sensitive to membrane voltage, mean open time increasing from 12 to 72 ms between \u201090 and 90 mV.<\/jats:p>","DOI":"10.1113\/jphysiol.1993.sp019531","type":"journal-article","created":{"date-parts":[[2014,12,17]],"date-time":"2014-12-17T14:51:55Z","timestamp":1418827915000},"page":"601-618","source":"Crossref","is-referenced-by-count":24,"title":["Single channel study of a Ca(2+)\u2010activated K+ current associated with ras\u2010induced cell transformation."],"prefix":"10.1113","volume":"461","author":[{"given":"Y","family":"Huang","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"S G","family":"Rane","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"311","published-online":{"date-parts":[[1993,2]]},"container-title":["The Journal of Physiology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/api.wiley.com\/onlinelibrary\/tdm\/v1\/articles\/10.1113%2Fjphysiol.1993.sp019531","content-type":"unspecified","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/physoc.onlinelibrary.wiley.com\/doi\/pdf\/10.1113\/jphysiol.1993.sp019531","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,10,25]],"date-time":"2023-10-25T05:43:00Z","timestamp":1698212580000},"score":1,"resource":{"primary":{"URL":"https:\/\/physoc.onlinelibrary.wiley.com\/doi\/10.1113\/jphysiol.1993.sp019531"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1993,2]]},"references-count":0,"journal-issue":{"issue":"1","published-print":{"date-parts":[[1993,2]]}},"alternative-id":["10.1113\/jphysiol.1993.sp019531"],"URL":"https:\/\/doi.org\/10.1113\/jphysiol.1993.sp019531","archive":["Portico"],"relation":{},"ISSN":["0022-3751","1469-7793"],"issn-type":[{"value":"0022-3751","type":"print"},{"value":"1469-7793","type":"electronic"}],"subject":[],"published":{"date-parts":[[1993,2]]}}}