Ier5, a novel member of the slow-kinetics immediate-early genes.
We describe here a novel member of the slow-kinetics immediate-early gene family. Ier5 is an intronless gene, encoding a serum- and growth factor-inducible message of 2123 nucleotides that is present in a wide variety of tissues. The predicted open reading frame encodes a 308-amino-acid, highly proline-rich protein with homology to the amino terminus of the immediate-early gene pip92/Ier2/ETR101. Ier5 is predicted to be a nuclear protein and contains a PEST-like sequence, suggesting rapid protein degradation. Multiple phosphorylation sites are present. Ier5 shows growth factor induction kinetics similar to that of pip92/Ier2/ETR101, but unlike pip92/Ier2/ETR101 does not appear to require phosphokinase C activity for transcriptional activation. The sequence of the promoter region of Ier5 was determined and examined for transcription factor binding sites thought to mediate serum and growth factor response. Multiple AP-1 sites and an Ets-1 site were observed, but the CArG and CArG-like boxes of the serum response element were absent. The predicted nuclear localization of Ier5, coupled with the potential for rapid regulation by phosphorylation and/or degradation, suggests that Ier5 may play an important role in mediating the cellular response to mitogenic signals.
Division of Population Science, Fox Chase Cancer Center, Philadelphia, Pennsylvania 19111, USA.
M
M
Williams
M S
MS
Lyu
Y L
YL
Yang
E P
EP
Lin
R
R
Dunbrack
B
B
Birren
J
J
Cunningham
K
K
Hunter
D016475:3T3 Cells; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D001923:Brain Chemistry / Q000235:genetics; D004305:Dose-Response Relationship, Drug; D017781:Genes, Immediate-Early / Q000235:genetics*; D006133:Growth Substances / Q000235:genetics / Q000494:pharmacology; D017874:Immediate-Early Proteins / Q000235:genetics*; D051379:Mice; D008969:Molecular Sequence Data; D009687:Nuclear Proteins; D017422:Sequence Analysis, DNA; D013997:Time Factors; D014157:Transcription Factors
D006133:Growth Substances; C118926:IER5 protein, human; C485574:Ier5 protein, mouse; D017874:Immediate-Early Proteins; D009687:Nuclear Proteins; D014157:Transcription Factors