P-type Ca2+-transporting ATPases are Ca2+ pumps, extruding cytosolic Ca2+ to the extracellular environment or the intracellular Ca2+ store lumens. In budding yeast, Pmr1 (plasma membrane ATPase related), and Pmc1 (plasma membrane calcium-ATPase) cannot be deleted simultaneously for it to survive in standard medium. Here, we deleted two putative Ca2+ pumps, designated AnPmrA and AnPmcA, from Aspergillus nidulans, and obtained the mutants ΔanpmrA and ΔanpmcA, respectively. Then, using ΔanpmrA as the starting strain, the promoter of its anpmcA was replaced with the alcA promoter to secure the mutant ΔanpmrAalcApmcA or its anpmcA was deleted completely to produce the mutant ΔanpmrAΔpmcA. Different from the case in Saccharomyces cerevisiae, double deletion of anpmrA and anpmcA was not lethal in A. nidulans. In addition, deletion of anpmrA and/or anpmcA had produced growth defects, although overexpression of AnPmc1 in ΔanpmrAalcApmcA could not restore the growth defects that resulted from the loss of AnPmrA. Moreover, we found AnPmrA was indispensable for maintenance of normal morphogenesis, especially in low-Ca2+/Mn2+ environments. Thus, our findings suggest AnPmrA and AnPmcA might play important roles in growth, morphogenesis and cell wall integrity in A. nidulans in a different way from that in yeasts.
In vivo cross-linking supports a head-to-tail mechanism for regulation of the plant plasma membrane P-type H+-ATPase
