Aged and post-mitotic cells share a very stable higher-order structure in the cell nucleus in vivo.
In the mammalian liver the quiescent primary hepatocytes preserve a proliferating potential in vivo, yet natural aging correlates with loss of proliferating potential and progression towards terminal differentiation of the hepatocytes. Thus aged, terminally-differentiated hepatocytes may survive in a de facto post-mitotic state, similarly to early post-mitotic cells, like neurons, suggesting that there might be a common factor linking both cellular states. In the interphase of metazoan cells the nuclear DNA is organized in supercoiled loops anchored to a proteinaceous substructure known as the nuclear matrix (NM). The DNA-NM interactions define a higher-order structure in the cell nucleus (NHOS). Natural aging of the rat liver correlates with a progressive strengthening of the NM framework and the stabilization of the DNA-NM interactions in the hepatocytes indicating that the NHOS becomes highly stable with age. We compared the NHOS of post-mitotic rat neurons with that of aged rat hepatocytes. Our results indicate that a very stable NHOS is a common feature of both aged and post-mitotic cells in vivo.
Universidad Autónoma del Estado de México, Toluca, Estado de Mexico, Mexico.
Janeth
J
Alva-Medina
Myrna A R
MA
Dent
Armando
A
Aranda-Anzaldo
D000375:Aging / Q000502:physiology*; D000818:Animals; D002467:Cell Nucleus / Q000737:chemistry / Q000378:metabolism; D004247:DNA / Q000737:chemistry / Q000378:metabolism; D022781:Hepatocytes / Q000166:cytology / Q000378:metabolism; D006801:Humans; D008297:Male; D015530:Nuclear Matrix / Q000737:chemistry / Q000378:metabolism; D009690:Nucleic Acid Conformation; D051381:Rats; D017208:Rats, Wistar
D004247:DNA