{'fraction_non_alphanumeric': 0.044585987261146494, 'fraction_numerical': 0.01795020266357846, 'mean_word_length': 4.647058823529412, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
cGMP-dependent Protein Kinase Iβ Physically and Functionally Interacts with the Transcriptional Regulator TFII-I*

Transcriptional regulation of the fospromoter by nitric oxide and cGMP can occur by nuclear translocation of cGMP-dependent protein kinase I (G-kinase I) (Gudi, T., Lohmann, S. M., and Pilz, R. B. (1997) Mol. Cell. Biol. 17, 5244–5254). To identify nuclear targets of G-kinase I, we performed a yeast two-hybrid screen with G-kinase Iβ as bait. We found that G-kinase Iβ interacted specifically with TFII-I, an unusual transcriptional regulator that associates with multiple proteins to modulate both basal and signal-induced transcription. By using purified recombinant proteins, the interaction was mapped to the N-terminal 93 amino acids of G-kinase Iβ and one of six 95-amino acid repeats found in TFII-I. In baby hamster kidney cells, cGMP analogs enhanced co-immunoprecipitation of G-kinase Iβ and TFII-I by inducing co-localization of both proteins in the nucleus, but in other cell types containing cytoplasmic TFII-I the G-kinase-TFII-I interaction was largely cGMP-independent. G-kinase phosphorylated TFII-I in vitro and in vivo on Ser371 and Ser743 outside of the interaction domain. G-kinase strongly enhanced TFII-I transactivation of a serum-response element-containing promoter in COS7 cells, and this effect was lost when Ser371 and Ser743 of TFII-I were mutated. TFII-I by itself had little effect on a full-length fospromoter in baby hamster kidney cells, but it synergistically enhanced transcriptional activation by G-kinase Iβ. Binding of G-kinase to TFII-I may position the kinase to phosphorylate and regulate TFII-I and/or factors that interact with TFII-I at the serum-response element.