Bridge-like lipid transfer protein family member 1 (BLTP1, formerly known as Tweek/KIAA1109 in human) is a tube-forming lipid transport protein which provides phosphatidylethanolamine for glycosylphosphatidylinositol (GPI) anchor synthesis in the endoplasmic reticulum. It plays a role in endosomal trafficking and endosome recycling and it is also involved in the actin cytoskeleton and cilia structural dynamics [2,3]. BLTP1 also acts as a regulator of phagocytosis [3]. Members of this entry belong to the repeating beta-groove (RBG) superfamily, conserved lipid transfer proteins containing long hydrophobic grooves [1]. They share the same structure comprising multiple repeating modules made of five beta-sheets followed by a loop [1,4]. This entry represents RBG modules found in the middle of BLTP1.

1: A novel superfamily of bridge-like lipid transfer proteins. Neuman SD, Levine TP, Bashirullah A; Trends Cell Biol. 2022;32:962-974. PMID:35491307

2: Endosomal trafficking defects in patient cells with KIAA1109 biallelic variants. Kane MS, Diamonstein CJ, Hauser N, Deeken JF, Niederhuber JE, Vilboux T; Genes Dis. 2019;6:56-67. PMID:30906834

3: Systematic Identification of Host Cell Regulators of Legionella pneumophila Pathogenesis Using a Genome-wide CRISPR Screen. Jeng EE, Bhadkamkar V, Ibe NU, Gause H, Jiang L, Chan J, Jian R, Jimenez-Morales D, Stevenson E, Krogan NJ, Swaney DL, Snyder MP, Mukherjee S, Bassik MC; Cell Host Microbe. 2019;26:551-563. PMID:31540829

4: Vps13-like proteins provide phosphatidylethanolamine for GPI anchor synthesis in the ER. Toulmay A, Whittle FB, Yang J, Bai X, Diarra J, Banerjee S, Levine TP, Golden A, Prinz WA; J Cell Biol. 2022; [Epub ahead of print] PMID:35015055