Emp47 and Vip36 are required for polarized growth and protein trafficking between ER and Golgi apparatus in opportunistic fungal pathogen Aspergillus fumigatus

In Aspergillus fumigatus, an opportunistic fungal pathogen causing fatal invasive aspergillosis, N-glycosylation is vital for polarized growth. To investigate its mechanism, two putative L-type lectin genes emp47 (AFUB_032470) and vip36 (AFUB_027870) were identified in A. fumigatus. Deletion of the emp47 or vip36 gene resulted in delayed germination and abnormal polarity. Also, the Delta emp47 displayed an increased resistance to azoles whereas the Delta vip36 showed an increased susceptibility to amphotericin B. Secretome analysis revealed that 205 proteins were differentially secreted in the Delta emp47 and 145 of them were reduced, while 153 proteins displayed a differential secretion and 134 of them were increased in the Delta vip36 as compared with that of the wild-type strain. Also, potential cargo glycoproteins of Emp47 and Vip36 were identified by comparative secretome analysis. Our results suggest that Emp47 is responsible for the transport of proteins from endoplasmic reticulum (ER) to Golgi, while Vip36 acts in protein retrieval from Golgi to ER.

Automated summary

The study revealed the important roles of Emp47 and Vip36 in Aspergillus fumigatus, with Emp47 responsible for protein transport from the endoplasmic reticulum (ER) to the Golgi, while Vip36 is involved in protein retrieval from the Golgi to the ER. The deletion of emp47 or vip36 genes affected germination, polarity, and drug susceptibility in A. fumigatus. Secretome analysis identified differential secretion of numerous proteins in the Delta emp47 and Delta vip36 mutants, suggesting their involvement in various cellular processes.