Autophagy-related protein required for cytoplasm to vacuole transport (Cvt) and autophagy as a part of the autophagy-specific VPS34 PI3-kinase complex I. This complex is essential to recruit the ATG8-phosphatidylinositol conjugate and the ATG12-ATG5 conjugate to the pre-autophagosomal structure. ATG38 is required for the integrity of the active PI3-kinase complex I by maintaining an association between VPS15-VPS34 and ATG1P-VPS30 subcomplexes. Homodimer. Component of the autophagy-specific VPS34 PI3-kinase complex I composed of VPS15, VPS30, VPS34, ATG14 and ATG38. Interacts directly with ATG14 and VPS34. Localization to the preautophagosomal structure requires ATG14.