Phosphorylation of nuclear proteins and proliferation in root meristems of pea (Pisum sativum)

A protein named QP47 has been purified from quiescent nuclei of root meristems of Pisum sativum, and used to prepare a polyclonal antibody. Immunolocalization of this protein with fluorescent probes revealed a nuclear distribution of thread-like structures. However, the relationship between the distribution of QP47 immunofluorescence and the structural organization of the chromatin required further investigation. The decrease in content of this protein in the nuclei of embryo cells seems to be correlated with the transition from quiescence to proliferation. QP47 degradation seems to depend upon an increase in the state of its phosphorylation. This protein is not present in normally proliferating cells, or in cells whose cell proliferation has been arrested by starvation or differentiation. It is hypothesized that QP47 may be required specifically during the quiescent period for specific structural organization of the chromatin.

show abstract

“…Two dimensional electrophoresis, SDS gel electrophoresis and protein phosphorylation were carried out according to Chiatante et al, (1991b).…”

Section: Gel Electrophoresis and Protein Phosphorylation Of Qp47mentioning

confidence: 99%

“…Having reported the presence of protein kinase activity in pea nuclei (Chiatante et al, 1991b), we were interested in investigating the phosphorylation state of QP47. In this regard, QP47 underwent phosphorylation in vitro and the level of phosphorylation remained constant at different times of germination (Fig.…”

Section: Properties and Localization Of Qp47mentioning

confidence: 99%