PsANT, the adenine nucleotide translocase of Puccinia striiformis, promotes cell death and fungal growth

Abstract

Adenine nucleotide translocase (ANT) is a constitutive mitochondrial component that is involved in ADP/ATP exchange and mitochondrion-mediated apoptosis in yeast and mammals. However, little is known about the function of ANT in pathogenic fungi. In this study, we identified an ANT gene of Puccinia striiformis f. sp. tritici (Pst), designated PsANT. The PsANT protein contains three typical conserved mitochondrion-carrier-protein (mito-carr) domains and shares more than 70% identity with its orthologs from other fungi, suggesting that ANT is conserved in fungi. Immuno-cytochemical localization confirmed the mitochondrial localization of PsANT in normal Pst hyphal cells or collapsed cells. Over-expression of PsANT indicated that PsANT promotes cell death in tobacco, wheat and fission yeast cells. Further study showed that the three mito-carr domains are all needed to induce cell death. qRT-PCR analyses revealed an in-planta induced expression of PsANT during infection. Knockdown of PsANT using a host-induced gene silencing system (HIGS) attenuated the growth and development of virulent Pst at the early infection stage but not enough to alter its pathogenicity. These results provide new insight into the function of PsANT in fungal cell death and growth and might be useful in the search for and design of novel disease control strategies.

TaCIPK10 interacts with and phosphorylates TaNH2 to activate wheat defense responses to stripe rust

“…Time points were selected based on a previous study (Wang et al ., ). For biological stress treatments, wheat seedlings were grown, inoculated and maintained as described previously (Tang et al ., ). For chemical treatments, 10‐day‐old wheat seedlings were sprayed with 2 m m salicylic acid (SA) dissolved in 0.1% (v/v) ethanol.…”

Tea polyphenol is a potential antifungal agent for the control of obligate biotrophic fungus in plants

“…The specimens were then cleared using saturated chloral hydrate until the leaf tissues became translucent. WGA conjugated to the fluorophore alexa 488 (Invitrogen) with a final concentration of 20 μg/ml was used to stain the leaf tissues as previously described (Tang et al., ). The lengths of the Pst germ tubes on wheat leaves were measured under an Olympus BX‐51 microscope (Olympus Corp., Tokyo, Japan).…”

Advances in understanding obligate biotrophy in rust fungi

“…A pipeline of diversified molecular approaches has been established to unravel the role of P. striiformis f. sp. tritici proteins during interaction with wheat and facilitated the study of more than 10 yellow rust genes over the past 5 years (Tang et al ., ,b; Tang et al ., ). Selected candidate genes are most often assayed by HIGS to validate their involvement in pathogenicity through quantitative estimation of infection‐related traits.…”

“…Depending on the given candidate, different complementary approaches were applied, such as subcellular localization in heterologous systems or in wheat protoplasts (Cheng et al ., , ; Wang et al ., ; Zhu et al ., ,b), complementation assays on yeast or fungal pathogens (Guo et al ., ; Liu et al ., ; Liu J. et al ., ; Zhu et al ., ), yeast invertase secretion assays (Cheng et al ., ; Liu J. et al ., ; Wang et al ., ), plant cell death BAX‐triggered suppression assays (Cheng et al ., ,b; Liu J. et al ., ) and overexpression in yeast coupled with the monitoring of stress responses (Cheng et al ., , ; Tang et al ., ,b; Jiao et al ., ; Zhu et al ., ,b). Among the proteins characterized through the aforementioned pipeline, six were identified as protein kinases or regulators of kinases in fungal transduction pathways (Guo et al ., ; Jiao et al ., ; Cheng et al ., , ; Qi, Zhu et al ., ) whereas others corresponded to a mitochondrial adenine nucleotide translocase antiporter (PsANT; Tang et al ., ,b), a superoxide dismutase (Liu J. et al ., ), an isocitrate lyase required for spore germination and one transcription factor. Two of the studied proteins were identified as candidate effectors (Cheng et al ., ; Wang et al ., ).…”