Global Analysis of Serine-Threonine Protein Kinase Genes in Neurospora crassa

Abstract

Serine/threonine (S/T) protein kinases are crucial components of diverse signaling pathways in eukaryotes, including the model filamentous fungus Neurospora crassa. In order to assess the importance of S/T kinases to Neurospora biology, we embarked on a global analysis of 86 S/T kinase genes in Neurospora. We were able to isolate viable mutants for 77 of the 86 kinase genes. Of these, 57% exhibited at least one growth or developmental phenotype, with a relatively large fraction (40%) possessing a defect in more than one trait. S/T kinase knockouts were subjected to chemical screening using a panel of eight chemical treatments, with 25 mutants exhibiting sensitivity or resistance to at least one chemical. This brought the total percentage of S/T mutants with phenotypes in our study to 71%. Mutants lacking apg-1, an S/T kinase required for autophagy in other organisms, possessed the greatest number of phenotypes, with defects in asexual and sexual growth and development and in altered sensitivity to five chemical treatments. We showed that NCU02245/stk-19 is required for chemotropic interactions between female and male cells during mating. Finally, we demonstrated allelism between the S/T kinase gene NCU00406 and velvet (vel), encoding a p21-activated protein kinase (PAK) gene important for asexual and sexual growth and development in Neurospora.

The Genomes of Three Uneven Siblings: Footprints of the Lifestyles of Three Trichoderma Species

“…T. reesei, T. atroviride, and T. virens also encode a second PKA catalytic subunit (PKAc2; TR_65873, TA_52331, and TV_214212), but its function has not been studied so far. However, in contrast to the severe phenotype of strains containing mutants for pkac1, homologs of this second PKA catalytic subunit do not show striking phenotypes (761), except for an alteration in growth of aerial hyphae (722).…”

“…Moreover, YPK1-like kinases are substrates of the TORC2 complex. Accordingly, the N. crassa and A. nidulans homologs were found to be essential as well (722,762). Misregulation of ypkA using conditional promoters in A. nidulans revealed a function of this gene in growth, sporulation, and branching.…”

“…The numbers of serine/ threonine (S/T) kinases range around 100 or more in fungi, fruit flies, and humans (719,721). The N. crassa genome contains 107 protein kinase genes, and a recent study showed that 9 of them are essential, and for about 70%, a phenotype was detected upon deletion (722), hence emphasizing the importance of this gene group.…”

“…Regulation by specific phospholipids as well as by autophosphorylation was observed (772). In N. crassa, their functions include regulation of growth and asexual and sexual development, as well as stress responses (722). For example, CAMK-1 is involved in regulation of growth and development, but also in circadian conidiation and phosphorylation of the circadian clock protein Frequency (FRQ) (773).…”

New Insights Into the Roles of NADPH Oxidases in Sexual Development and Ascospore Germination in Sordaria macrospora

“…Display rate, 1 frame /12 s. Related to Figure 5C. ; b (Berepiki et al 2011); c (Dagdas et al 2012); d (Chen and Thorner 2007); e (Semighini and Harris 2008); f (Jones and Bennett 2011); g ; h (Artiles et al 2009); i (Das et al 2013); j (Rank and Rayment 2013); k (Krappmann et al 2007); l (Pulver et al 2013); m (Park et al 1997); n (Brace et al 2011); o (Knaus et al 2007); p (Berepiki and Read 2013) (Glass and Lee 1992); g (Ferreira et al 1998); h (Hammond et al 2012); i (Li et al 2005); j (Park et al 2011) …”