FosB gene products trigger cell proliferation and morphological alteration with an increased expression of a novel processed form of galectin-1 in the rat 3Y1 embryo cell line.
In this study, we established rat 3Y1 embryo cell lines expressing FosB and DeltaFosB as fusion proteins (ER-FosB, ER-DeltaFosB) with the ligand-binding domain of human estrogen receptor (ER). The binding of estrogen to the fusion proteins resulted in their nuclear translocation. After estrogen administration, exponentially growing cells expressing ER-DeltaFosB, and to a lesser extent ER-FosB, underwent morphological alteration from the flat fibroblastic shape to an extended bipolar shape, and ceased proliferating. Such morphological alteration was also induced in quiescent cells expressing ER-DeltaFosB and ER-FosB after one round of cell division triggered by estrogen administration. The cells expressing ER-DeltaFosB changed shape frequently, and the content of F-actin in the cytoplasm detected by binding of Alexa 488-phalloidin significantly decreased after the morphological alteration. By two-dimensional gel electrophoresis analysis of cellular proteins from the cells expressing ER-DeltaFosB, we identified several proteins whose expression either increased or decreased after estrogen administration. Two of these proteins were identified from their amino acid sequences as novel processed form of galectin-1.
Nishioka
Tomoko
T
Division of Neurofunctional Genomics, Medical Institute of Bioregulation, Kyushu University, and CREST, Japan Science and Technology Corporation, Maidashi, Higashi-ku, Fukuoka 812-8582.
Sakumi
Kunihiko
K
Miura
Tomofumi
T
Tahara
Kazuki
K
Horie
Hidenori
H
Kadoya
Toshihiko
T
Nakabeppu
Yusaku
Y
D000199:Actins / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D015180:Electrophoresis, Gel, Two-Dimensional; D004622:Embryo, Mammalian; D004967:Estrogens / Q000494:pharmacology; D037483:Galectin 1 / Q000096:biosynthesis* / Q000235:genetics; D005786:Gene Expression Regulation; D006801:Humans; D008856:Microscopy, Fluorescence; D008858:Microscopy, Phase-Contrast; D008969:Molecular Sequence Data; D016760:Proto-Oncogene Proteins c-fos / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*; D051381:Rats; D011960:Receptors, Estrogen / Q000235:genetics / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis / Q000235:genetics; D013997:Time Factors
D000199:Actins; D004967:Estrogens; D037483:Galectin 1; D016760:Proto-Oncogene Proteins c-fos; D011960:Receptors, Estrogen; D011993:Recombinant Fusion Proteins