Protein Phosphorylation Notes References sites Transcription AML1 Ser249, Ser266 Phosphorylation of the acute myelogenous leukemia 1 (AML1) potentially regulates its (Tanaka et al., 1996) Factors (RUNX1) transactivation potential and thereby modifies myeloid hematopoietic differentiation. Androgen Ser514 Phosphorylation of androgen receptor by ERKs is controversial. May play a role in survival (Yeh et al., 1999) receptor and proliferation of prostate cells. Arix/Phox2a Ser36, Ser71 Phosphorylation of Arix by ERK1/2 inhibits its ability to interact with target genes. (Hsieh et al., 2005) ATF2 Thr71 This phosphorylation together with the phosphorylation of Thr69 by p38MAPK induces (Ouwens et al., 2002) activation of ATF2. Beta2 (Neuro Ser274 Phosphorylation of this HLH transcription factor induces its glucose-sensitive transactivation (Khoo et al. 2003) D1) and enhances its capability to heterodimerize with E47/12 and bind to DNA. BCL-6 Ser333, Ser343 Phosphorylation of BCL-6 induces its degradation that is important for B-cell differentiation (Niu et al., 1998) and antibody response. BMAL1 Ser527, Thr534, Phosphorylation of this helix-loop-helix-PAS transcription factor inhibits its activity as a clock (Sanada et al., 2002) Ser599 (chicken) oscillator. CBP Thr188 Phosphorylation of the C-terminal region of the CREB binding protein (CBP, and also its (Janknecht and homolog p300) enhances its transactivation potential. Nordheim, 1996) C/EBPb Thr188 (rat) Phosphorylation of the CCAAT/enhancer-binding protein-b (C/EBPb) by ERK2 (not ERK1) (Hanlon et al., 2001) enhances its interaction with SRF and its transactivation activity. CRY1/2 Ser265, Ser557 Phosphorylation of the Cryptochromes proteins CRY1 and 2 results in attenuation of their (Sanada et al., 2004) (CRY1, mouse) ability to inhibit BMAL1:CLOCK-mediated transcription. E47/E12 Ser352, Thr355, Phosphorylation of E47/E12 regulates its heterodimerization with Beta2 and subsequent DNA (Khoo et al. 2003) Ser359 binding. Elk1 Ser324?, Thr336? Phosphorylation of this Ets transcription factor enhances its activity, which is mainly the (Gille et al., 1992) Thr353, Thr363, Thr- transcription of c-Fos. (Cruzalegui et al., 1999) 368, Ser383, Ser389, Thr417,Ser422? ER81 Ser94, Thr139, Thr- Phosphorylation of this Ets transcription factor induces its activity and thereby regulates (Janknecht, 1996) 143, Ser146, Ser152, developmental processes. Thr158 (mouse) - 1 - Protein Phosphorylation Notes References sites Transcription ERF Thr526 (mouse) Phosphorylation of this Ets transcription factor decreases its transcriptional repression and (Sgouras et al., 1995) Factors thereby regulates differentiation. Estrogen Ser118 Phosphorylation of the estrogen receptor results in its activation and propagation of estrogen (Kato et al., 1995) receptor signaling. c-Fos Thr325, Thr331, Phosphorylation stabilizes the c-Fos protein, and is required for its maximal transactivation. It (Murphy et al., 2002) Ser374 plays a role as a sensor for ERKs’ signal duration. Fra-1 Thr231 (mouse) Phosphorylation enhances DNA binding of Fra-1, and is required for its participation in AP-1 (Young et al., 2002) transactivation. GATA-1/2 Ser26, Ser178 This phosphorylation increases the protein-protein interaction of GATA-1, and is involved in (Towatari et al., 2004) (GATA-1) the regulation of differentiation and development of erythroid cells. HIF-1a Phosphorylation enhances the transcriptional activity of hypoxia induced factor1a (HIF-1a). (Richard et al., 1999) HSF-1 Ser307 Phosphorylation of the heat shock factor-1 (HSF-1) represses its transcriptional activation. (Chu et al., 1996) ICER Ser41 (rat) Phosphorylation of inducible cAMP early repressor (ICER) targets it to ubiquitination and (Yehia et al., 2001) degradation. c-Jun Ser63, Ser73, Ser243 Phosphorylation of Ser63 and Ser73 induces the transcriptional activity of c-Jun. The (Morton et al., 2003) phosphorylation of Ser243 may participate in its downregulation. Microph- Ser73 Phosphorylation of Mi (also termed MITF) leads to its activation and subsequent degradation (Wu et al., 2000) thalmia (Mi) that are essential for melanocyte development. c-Myc Ser62 It is not clear whether this activatory phosphorylation occurs in vivo. (Alvarez et al., 1991) N-Myc Ser51 Phosphorylation is required for the transcriptional repression activity of N-Myc. (Manabe et al., 1996) Net (Sap-2) Ser365, possibly Phosphorylation of this Ets transcription factor participates in converting its activity from (Price et al., 1995) other (mouse) repression to activation. NFATc4 Ser676 Phosphorylation of the nuclear factor of activated T cells (NFAT) is involved in assembly of (Yang et al., 2005) its transcription complex. NF-IL6 Thr235 Phosphorylation of the nuclear factor for IL6 (NF-IL6), which is a member of the C/EBP (Nakajima et al., 1993) family (see above), stimulates its transactivation potential. - 2 - Protein Phosphorylation Notes References sites Transcription NGFI-B/TR3/ Thr142 Phosphorylation of this factor probably inhibits its proapoptotic action. (Slagsvold et al., 2002) factors Nur77 Pax6 Ser413 (zebrafish) Phosphorylation enhances transactivation activity of Pax6 that is important for the (Mikkola et al., 1999) development of the central nerve system. PDX-1 Ser61, Ser66 The homeodomain-containing transcription factor PDX-1 regulates transactivation activities. (Khoo et al. 2003) PPARg Ser84 (PPARg1), Ser- Phosphorylation of the peroxisome proliferators-activated receptor g (PPARg) inhibits its (Hu et al., 1996) 112 (PPARg2, mouse) activity and suppresses adipogenesis. p53 Thr73, Thr83 (mice), Phosphorylation of Thr55 is necessary for doxorubicin-induced p53 activation and cell death. (Milne et al., 1994; Yeh Thr55 (human) The role of the other phosphorylations of theis tumor suppressor protein is not entirely clear. et al., 2004) Progesterone Ser294 Phosphorylation of this nuclear receptor leads to its proteosomal degradation and inhibits (Lange et al., 2000) receptor progesterone signaling. ( c-Rel Ser451 (mouse) It is not clear whether the phosphorylation is by ERK or another proline directed kinase. Fognani et al. 2000 RNA Multiple sites Phosphorylation of the C-terminal of this protein induces its transcriptional activity. (Markowitz et al., 1995) polymerase-II RUNX2 Ser14? Phosphorylation of RUNX2 is required for responsiveness of osteoblasts to extracellular (Xiao et al., 2000) matrix signals. Sap-1 Ser381, Ser387 Phosphorylation activates this Ets transcription factor and thereby facilitates IEG transcription. (Janknecht et al., 1995) Smad1 Ser187, Ser195, Phosphorylation inhibits nuclear accumulation of Smad1 and its TGF-b -induced (Kretzschmar et al., Ser206, Ser214 transcriptional activity. 1997) Smad2/3 Thr220, Ser245, Phosphorylation of Smad2/3 inhibits TGF-b-induced transcription. (Kretzschmar et al., Ser250, Ser255 1999) (Smad 2) Smad4 Thr276 Phosphorylation of Smad4 accelerates the rate of its nuclear accumulation and therefore (Roelen et al., 2003) facilitates its TGF-b-induced transcriptional activity. SP-1 Thr453, Thr739 Phosphorylation of this transcription factor stimulates its DNA binding and increases VEGF (Merchant et al., 1999) expression in fibroblasts. (Milanini-Mongiat et al., 2002) - 3 - Protein Phosphorylation Notes References sites Transcription SRC-1 Ser395, Thr1179, Phosphorylation of the steroid receptor coactivator 1 (SRC-1) stimulates its ligand-dependent, (Rowan et al., 2000) factors Ser1185 and progesterone receptor-mediated activity. SREBP1/2 Ser432, Ser455 Phosphorylation of the sterol regulatory element binding protein (SREBP) enhances its (Kotzka et al., 2000) (SREBP2) transactivation activity. STAT1/3 Ser727 (mouse) Phosphorylation of the signal transducers and activators of transcription (Stats) inhibits their (Chung et al., 1997) tyrosine phosphorylation and thereby their transcriptional activity. STAT5a Ser780 Phosphorylation of Stat5a prevents its nuclear translocation and its transcriptional activity. (Pircher et al., 1999) TAL-1/SCL Ser122 Phosphorylation of the T-cell acute lymphocytic leukemia 1 (TAL-1) enhances its (Cheng et al., 1993) transactivation activity. TFII-I Ser627, Ser633 Phosphorylation of the transcription initiation factor (TFII-I) facilitates its transcriptional (Kim and Cochran, activity on the c-Fos promotor. 2000) TFIIIB Thr145 Phosphorylation of the RNA polymerase IIIB (TFIIIB) stimulates its activity and induces (Felton-Edkins et al., synthesis of tRNA. 2003) TGIF Thr235, Thr239 Phosphorylation of the TGFg inhibitory factor (TGIF), which is a Smad co-repressor, leads to (Lo et al., 2001) the stabilization of TGIF, and to the formation of TGIF-Smad2 co-repressing complexes. TIF-1A Ser633 Phosphorylation of the RNA-Polymerase specific transcription initiation factor (TIF)-IA is (Zhao et al., 2003) required for RNA Polymerase I transcription and cell growth. Tob Ser152, Ser154, Phosphorylation of this protein probably prevents its anti-proliferative activity. (Maekawa et al., 2002) Ser164 UBF Thr117, Thr201 (rat) Phosphorylation of this so-called upstream binding factor (UBF), which is a multiple HMG box (Stefanovsky et al., architectural factor, prevents its interaction with DNA and allows ribosomal transcription. 2001) Kinases and Phosphatases DAPK Ser735 Phosphorylation of the death associated protein kinase (DAPK) promotes apoptosis. DAPK (Chen et al., 2005) also anchors ERKs in the cytosol. ERK1/2 Tyr185 (ERK2) The role of the autophosphorylation is not clear. Can be followed by a slow Thr183 (Seger