Clonal cells from embryonic retinal cell lines express qualitative electrophysiological differences.
Cells from the embryonic quail retina were immortalized with the v-mil oncogene and cloned by limiting dilution. Their phenotype was examined using the whole-cell patch clamp method. Three membrane currents, IK(IR), INa and IK, were found at different frequencies within a sample of 170 cells drawn from a large clone. Nearly all combinations of these three markers were found and the frequency of combinations showed that the markers assorted independently. Examination of clones of less than 10 cells showed that heterogeneity originates with a high probability within clones, arguing that chromosomal mutation, for example, is unlikely to account for phenotypic diversity. A possible explanation is that phenotypic differences between cells might reflect the local exchange of instructive signals. If so, then the genes for the three phenotypic markers are controlled independently.
Lenzi
D
D
Department of Zoology, University of California, Davis 95616.
Radke
K
K
Wilson
M
M
D000818:Animals; D001354:Avian Leukosis Virus / Q000235:genetics; D002461:Cell Line, Transformed; D002472:Cell Transformation, Viral; D002999:Clone Cells / Q000502:physiology; D003370:Coturnix / Q000196:embryology; D004594:Electrophysiology; D005814:Genes, Viral; D015640:Ion Channel Gating; D007473:Ion Channels / Q000378:metabolism; D008564:Membrane Potentials; D009857:Oncogenes; D010641:Phenotype; D011188:Potassium / Q000378:metabolism; D012160:Retina / Q000196:embryology* / Q000502:physiology; D012964:Sodium / Q000378:metabolism; D015678:Viral Structural Proteins / Q000235:genetics
D007473:Ion Channels; D015678:Viral Structural Proteins; D012964:Sodium; D011188:Potassium