Here, we further investigate the functions of protein phosphatases in A. fumigatus by generating a null mutant collection for the phosphatase catalytic subunit encoding genes.
Deletion of GOA1, achieved by constructing a null mutant, causes loss of chronological aging, constitutive yeast growth, lethal levels of ROS, apoptosis, heightened susceptibility to triazole antifungal drugs, and reduced energy production from both mitochondria and peroxisomes.
By analyzing a null mutant of the rice RDR1 gene (OsRDR1), we showed that expression of more than 1,000 endogenous genes of diverse gene ontology (GO) categories were significantly altered in the mutant, indicating a functional role of OsRDR1 in regulating endogenous gene expression in rice.
In contrast to the approach of disabling a gene by creating a large deletion, the production of a null mutant by such a small intervention would be unlikely to cause collateral damage.
In order to address the function of PGRP-SB1 in vivo, we aimed to generate a null mutant by homologous recombination.
We therefore attempted to generate a null mutant by imprecise excision of this P-element (see Materials and Methods).
To determine the function of sigmar during development, we created a null mutant by P-element imprecise excision.
To investigate an enhanced or specialized role for rab7 in the nervous system, we generated a null mutant by replacing the rab7 open reading frame with a Gal4 knock-in cassette; the Gal4 knock-in provides a means to express any gene of interest under the endogenous regulatory elements of rab7 in either heterozygous or homozygous rab7 mutants (Brand and Perrimon, 1993; Chan et al., 2011, 2012).
A null mutant generated by double crossing over was identified by its apramycin-resistant and kanamycin-sensitive phenotype and named SV77 after confirmation by PCR using test primers listed in Table S4.
In this case, repeated failures in obtaining a null mutant line by gene-replacement point to an essential role of this protein for proliferation of the parasite [ 61].
