Plays a role in autophagy (PubMed:26442587). Functions at the preautophagosomal structure (PAS) in order to form normal autophagosomes under starvation conditions (By similarity). Also plays a role in mitophagy (By similarity). Forms a stable complex with ATG17 and ATG31 (By similarity). Interacts directly with ATG31 (By similarity). The ATG17-ATG29-ATG31 complex interacts with the ATG1-ATG13 complex (By similarity). Note=The interaction with the ATG1-ATG13 complex is induced by starvation (By similarity). Localizes also to other perivacuolar punctate structures (By similarity). Mislocalizes ATG8 in the cytosol, when ATG11 is also deleted (PubMed:26442587). Kluyveromyces marxianus proteins are shorter in length and have a more ordered secondary structure than their S.cerevisiae counterparts, which might contribute to the superior thermotolerance and solubility (PubMed:26442587). K.marxianus could be therefore useful as a new model organism for further elucidation of the molecular details of autophagy (PubMed:26442587). Belongs to the ATG29 family.