5a). In the control strain, approximately 70% of hyphae contained stained Spk 30 min after the initial staining (Fig. 5b and c), which increased to 90% after 60 min (Fig. 5b). In contrast, in the

aipA-overexpressing strain, approximately 35% of hyphae with stained Spk were observed 30 min after the staining (Fig. 5b and c), which only increased to 50% after 60 min (Fig. 5b). Notably, the mutant aipA-overexpressing strains showed nearly identical Spk staining as that of the control selleck products strain (Fig. 5b and c). Taken together, these results suggest that the endocytic recycling of FM4-64 to Spk is both defective and delayed in the aipA-overexpressing strain. However, because the aipA-overexpressing strain also displayed impaired growth, it is possible that the Spk was not present in certain hyphae,

and thus, the relative rate of endocytic recycling was not substantially delayed in this strain. To exclude this possibility, we calculated the half-time required for Spk staining with FM4-64 for each of the strains (Fig. 5d). The half-time for staining in the aipA-overexpressing strain was clearly longer than that in the control and mutant aipA-overexpressing strains, indicating that the learn more aipA-overexpressing strain has defects with respect to endocytic recycling; this delay could be caused by the defect of endocytosis, that of trafficking of vesicles to Spk, or both. We also confirmed that there was no significant difference between the control and the ΔaipA strains in this analysis (data not shown). In this study, we discovered a putative

AAA ATPase, AipA, as a binding partner of AoAbp1 by YTH screening. Although the ΔaipA strain did not display growth or endocytic defects, the aipA-overexpressing strain showed impaired growth, abnormal hyphal morphology, and a deficiency in the endocytic recycling of FM4-64, whereas the mutant aipA-overexpressing strains did not. The subsequent localization and functional analyses using the aipA-overexpressing strain suggested that AipA negatively functions Thymidylate synthase in endocytic recycling at the tip region of A. oryzae. There seems to be one AipA ortholog in filamentous fungi and two in yeasts. Both Sap1p and Yta6p, S. cerevisiae AipA orthologs, are putative AAA ATPases, but their molecular function is unknown. Sap1p was found by the YTH analysis as a binding protein with Sin1p, a transcriptional repressor (Liberzon et al., 1996). Yta6p is one of 12 YTA family proteins and is localized at the cortex in mother cells, but not in daughter cells (Schnall et al., 1994; Beach & Bloom, 2001). Single disruptants of either SAP1 or YTA6 are viable and no remarkable phenotypic alteration has been reported.