Unconventional secretion of nigerolysins A from Aspergillus species

Kraševec, Nada (author), Novak, Maruša (author), Barat, Simona (author), Skočaj, Matej (author), Sepčić, Kristina (author), Anderluh, Gregor (author)

Aegerolysins are small lipid-binding proteins particularly abundant in fungi. Aegerolysins from oyster mushrooms interact with an insect-specific membrane lipid and, together with MACPF proteins produced by the same organism, form pesticidal pore-forming complexes. The specific interaction with the same membrane lipid was recently demonstrated for nigerolysin A2 (NigA2), an aegerolysin from Aspergillus niger. In Aspergillus species, the aegerolysins were frequently found as secreted proteins, indicating their function in fungal defense. Using immunocytochemistry and live-cell imaging we investigated the subcellular localization of the nigerolysins A in A. niger, while their secretion was addressed by secretion prediction and Western blotting. We show that both nigerolysins A are leaderless proteins that reach the cell exterior by an unconventional protein secretion. NigA proteins are evenly distributed in the cytoplasm of fungal hyphae. A detailed bioinformatics analysis of Aspergillus aegerolysins suggests that the same function occurs only in a limited number of aegerolysins. From alignment, analysis of chromosomal loci, orthology, synteny, and phylogeny it follows that the same or a similar function described for pairs of pesticidal proteins of Pleurotus sp. can be expected in species of the subgenus Circumdati, section Nigri, series Nigri, and some other species with adjacent pairs of putative pesticidal proteins.

• Language: English
• Keywords: aegerolysin, nigerolysin, membrane-attack-complex/perforin (MACPF) protein, Aspergillus, Fungi, bioinformatics, localization, unconventional secretion, ceramide phosphoethanolamine (CPE), invertebrate lipid binding
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: BF - Biotechnical Faculty
• Publication status: Published
• Publication version: Version of Record
• Year: 2020
• Number of pages: 23 str.
• Numbering: Vol. 8, iss. 12, art. 1973
• PID: 20.500.12556/RUL-134669
• UDC: 577
• ISSN on article: 2076-2607
• DOI: 10.3390/microorganisms8121973
• COBISS.SI-ID: 42464771
• Publication date in RUL: 25.01.2022

Record is a part of a journal

• Title: Microorganisms
• Shortened title: Microorganisms
• Publisher: MDPI AG
• ISSN: 2076-2607
• COBISS.SI-ID: 523277081

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.
• Licensing start date: 11.12.2020

Secondary language

• Language: Slovenian
• Keywords: egerolizin, nigerolizin, MACPF-protein, Aspergillus, glive, bioinformatika, lokalizacija, nekonvencionalna sekrecija, ceramid fosfoetanolamin, vezava na nevretenčarske lipide