title: Lst4, the yeast Fnip1/2 orthologue, is a DENN-family protein.
abstract: The folliculin/Fnip complex has been demonstrated to play a crucial role in the mechanisms underlying Birt-Hogg-Dubé (BHD) syndrome, a rare inherited cancer syndrome. Lst4 has been previously proposed to be the Fnip1/2 orthologue in yeast and therefore a member of the DENN family. In order to confirm this, we solved the crystal structure of the N-terminal region of Lst4 from Kluyveromyces lactis and show it contains a longin domain, the first domain of the full DENN module. Furthermore, we demonstrate that Lst4 through its DENN domain interacts with Lst7, the yeast folliculin orthologue. Like its human counterpart, the Lst7/Lst4 complex relocates to the vacuolar membrane in response to nutrient starvation, most notably in carbon starvation. Finally, we express and purify the recombinant Lst7/Lst4 complex and show that it exists as a 1 : 1 heterodimer in solution. This work confirms the membership of Lst4 and the Fnip proteins in the DENN family, and provides a basis for using the Lst7/Lst4 complex to understand the molecular function of folliculin and its role in the pathogenesis of BHD syndrome.
authors.affiliation: Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge CB2 1GA, UK ap681@cam.ac.uk.
authors.forename: Angela
authors.initials: A
authors.lastname: Pacitto
authors.affiliation: Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge CB2 1GA, UK.
authors.forename: David B
authors.initials: DB
authors.lastname: Ascher
authors.affiliation: Department of Cell Biology, UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK.
authors.forename: Louise H
authors.initials: LH
authors.lastname: Wong
authors.affiliation: Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge CB2 1GA, UK.
authors.forename: Beata K
authors.initials: BK
authors.lastname: Blaszczyk
authors.affiliation: Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge CB2 1GA, UK.
authors.forename: Ravi K
authors.initials: RK
authors.lastname: Nookala
authors.affiliation: Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge CB2 1GA, UK.
authors.forename: Nianshu
authors.initials: N
authors.lastname: Zhang
authors.affiliation: CNRS UMR 8126, Université Paris-Sud 11, Institut Gustave Roussy, 114, rue Edouard Vaillant, Villejuif 94805, France.
authors.forename: Svetlana
authors.initials: S
authors.lastname: Dokudovskaya
authors.affiliation: Department of Cell Biology, UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK.
authors.forename: Tim P
authors.initials: TP
authors.lastname: Levine
authors.affiliation: Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge CB2 1GA, UK tlb20@cam.ac.uk.
authors.forename: Tom L
authors.initials: TL
authors.lastname: Blundell
mesh_terms: D005656:Fungal Proteins / Q000737:chemistry* / Q000378:metabolism*; D007716:Kluyveromyces / Q000378:metabolism*; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry / Q000378:metabolism; D033921:Vesicular Transport Proteins / Q000737:chemistry / Q000378:metabolism
chemical_list: D005656:Fungal Proteins; C513355:LST4 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D033921:Vesicular Transport Proteins
keywords: BHD syndrome; DENN-family; Fnip1/2; Lst4; Lst7; folliculin