H-ras gene is expressed at the G1 phase in primary cultures of hepatocytes.
The expression of c-H-ras and proliferating cell nuclear antigen (PCNA) in primary cultures of rat hepatocytes was determined in order to elucidate the relationship between the c-H-ras gene and the S phase of the cell cycle. In cells treated with EGF, elevation of c-H-ras expression was detected at the 22nd, 34th, 44th, and 54th h after plating, PCNA expression and DNA synthesis were detected at the 44th and 54th h. In cells without EGF treatment, only c-H-ras expression was detected at the 44th and 54th h. In our previous report, we showed that c-myc expression increased within several hours after plating, suggesting that isolated hepatocytes traverse from G0 to G1 under culture conditions, regardless of EGF treatment. These results clearly showed that the c-H-ras gene of adult rat hepatocytes was expressed in the mid-to-late G1 phase of the cell cycle as well as in the early S phase in primary culture.
Ikeda
T
T
Department of Pathology, Sapporo Medical College, Japan.
Sawada
N
N
Fujinaga
K
K
Minase
T
T
Mori
M
M
D000818:Animals; D002478:Cells, Cultured; D015870:Gene Expression; D007399:Interphase; D008099:Liver / Q000166:cytology* / Q000378:metabolism; D008297:Male; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism; D018809:Proliferating Cell Nuclear Antigen; D011518:Proto-Oncogene Proteins / Q000235:genetics* / Q000378:metabolism; D016283:Proto-Oncogene Proteins p21(ras); D051381:Rats; D011916:Rats, Inbred F344
D009687:Nuclear Proteins; D018809:Proliferating Cell Nuclear Antigen; D011518:Proto-Oncogene Proteins; D016283:Proto-Oncogene Proteins p21(ras)