Beclin1 is the first identified mammalian autophagy-related protein and serves as a scaffold protein in the Class Ⅲ Phosphatidylinositol 3-Kinase VPS34 complex.The functional role of Beclin1 depends on its interactions with other autophagic regulators.The coiled coil domain of Beclin1 is critical for recruitment of autophagy regulators including Atg14L to form subcomplexes promoting autophagy.Our findings suggest the metastability of Beclin1 coiled coil is of great importance for the shift from Beclin1 homodimer to Beclin1-Atg14L heterodimer,driven by the dynamic exchange.We identified a unique structural feature of the Beclin1 coiled coil domain and helped to explain how Beclin1 can utilize its coiled coil domain to recruit a variety of autophagy regulators to form functionally distinct enzyme complexes in response to specific autophagy signal.We also modified the structural elements on the homodimer interface to find the Beclin1-Atg14L heterodimer formation can be strengthened or weakened as expected.These findings provide novel insight into the intricate network of autophagy regulation and may help to conceive new strategies to target autophagy for disease treatment.