T. Davidpfeuty et Y. Nouviandooghe, HIGHLY SPECIFIC ANTIBODY TO ROUS-SARCOMA VIRUS SRC GENE-PRODUCT RECOGNIZES NUCLEAR AND NUCLEOLAR ANTIGENS IN HUMAN-CELLS, Journal of virology, 69(3), 1995, pp. 1699-1713
An antiserum to the Rous sarcoma virus-transforming protein pp60(v-src
), raised in rabbits immunized with the bacterially produced protein a
lpha p60 serum (M. D. Resh and R L. Erikson, J. Cell Biol. 100:409-417
, 1985) previously reported to detect very specifically a novel popula
tion of pp60(v-src) and pp6(c-src) molecules associated with juxtareti
cular nuclear membranes in normal and Rous sarcoma virus-infected cell
s of avian and mammalian origin, was used here to investigate by immun
ofluorescence microscopy localization patterns of src molecules in hum
an cell lines, either normal or derived from spontaneous tumors. We fo
und that the alpha p60 serum reveals nuclear and nucleolar concentrati
ons of antigens in all the human cell Lines tested and in two rat and
mouse hepatoma cell lines derived from adult tumorous tissues but not
in any established rat and mouse cell lines either untransformed or tr
ansformed lay the spe and ras oncogenes, Both the nuclear and nucleola
r stainings can be totally extinguished by preincubation of the serum
with highly purified chicken c-Src; We show also that the partitioning
of the alpha p60-reactive proteins among the whole nucleus and the nu
cleolus depends mostly on two different parameters: the position in th
e cell cycle and the degree of cell confluency. Our observations raise
the attractive possibility that, in differentiated cells, pp60(c-src)
and related proteins plight be involved not only in mediating the tra
nsduction of mitogenic signals at the plasma membrane level but also i
n controlling progression through the cell cycle and entry in mitosis
by interacting with cell division cycle regulatory components at the n
uclear level.