High impact information on TPK2

• We have isolated three genes (TPK1, TPK2, and TPK3) from the yeast S. cerevisiae that encode the catalytic subunits of the cAMP-dependent protein kinase [1].
• Saccharomyces cells secrete aromatic alcohols that stimulate morphogenesis by inducing the expression of FLO11 through a Tpk2p-dependent mechanism [2].
• Residual derepression in a cAMP-nonresponsive mutant with attenuated protein kinase activity (bcy1 tpk1w tpk2 tpk3) demonstrates the existence of an alternative, cAMP-independent nutrient signaling mechanism [3].
• Tpk2 negatively regulates genes involved in iron uptake and positively regulates genes involved in trehalose degradation and water homeostasis [4].
• We demonstrate that they have dramatically different roles in pseudohyphal development: Tpk2 is essential, whereas Tpk3 inhibits [5].

Biological context of TPK2

• TPK1 and TPK2 encode both isoforms of protein kinase A (PKA) catalytic subunits in Candida albicans [6].
• Introduction of a plasmid carrying the TPK1 or TPK2 gene into tpk1tpk2TPK3 cells restores the heat-induced increase of neutral trehalase activity [7].
• In contrast, tpk2 mutants were only partially morphogenesis defective on solid media, whereas a strong block was observed in liquid [6].
• These data suggest that TPK2 executes an essential function in T. gondii cell cycle and is likely to be the T. gondii CDC2 orthologue [8].
• Deletion of TPK2 blocks morphogenesis and partially reduces virulence, whereas TPK2 overexpression induces hyphal formation and stimulates agar invasion [9].

Associations of TPK2 with chemical compounds

• The morphogenetic behavior of several C. albicans mutant strains bearing one or both BCY1 alleles, in a wild-type and in a TPK2 null genetic background, was assessed in N-acetylglucosamine (GlcNAc) liquid medium at 37 degrees C. Strains with one BCY1 allele tagged or not, behaved similarly, displaying pseudohyphae and true hyphae [10].
• TPK2 complements the growth defect of a Saccharomyces cerevisiae tpk1-3 mutant and Tpk2p is able to phosphorylate an established PKA-acceptor peptide (kemptide) [9].
• Glucose-induced inactivation of isocitrate lyase in Saccharomyces cerevisiae is mediated by the cAMP-dependent protein kinase catalytic subunits Tpk1 and Tpk2 [11].

Physical interactions of TPK2

• Sfl1 is known to interact with Tpk2, a cAMP-dependent protein kinase that negatively regulates Sfl1 function [12].

Regulatory relationships of TPK2

• The counter-selectable markers consist of the PKA3 gene under control of the conditional MET25 or CHA1 promoters [13].

Other interactions of TPK2

• Because Tpk1p and Tpk2p differ in their N-terminal domains of approximately 80--90 amino acids, while the catalytic portions are highly homologous, the functions of hybrid Tpk proteins with exchanged N-terminal domains were tested [6].
• Three genes TPK1, TPK2 and TPK3 encode in Saccharomyces cerevisiae distinct catalytic subunits of cAMP-dependent protein kinase (cAPK) [14].
• In phosphorylation of Pyk1 mainly the Tpk2 catalytic subunit of yeast PKA was involved [15].
• Diploid cells lacking Gpr1p, Plc1p, or Gpa2p fail to form pseudohyphae upon nitrogen depletion, and the filamentation defect of gpr1Delta and plc1Delta strains is rescued by activating a mitogen-activated protein kinase pathway via STE11-4 or by activating a cAMP pathway via overexpressed Tpk2p [16].
• The Sch9p kinase was not required for the signal generated by deletion of KRH1 and KRH2; however, the cAMP-dependent kinase Tpk2p was required for generation of this signal [17].

Analytical, diagnostic and therapeutic context of TPK2

• TPK2 tagged with HA epitope (TPK2-HA-wt) was expressed in mammalian cells as confirmed by Western blot analysis using HA tag and PSTAIRE antibodies [8].

References