MAP1LC3B and Langer mesomelic dysplasia: To further investigate the molecular aspects of LMD, we carried out complementation experiments using LC3B siRNA (which targets the 3′UTR of endogenous LC3B) and FLAG-tagged LC3B or its variants (Fig. 5a): FLAG-proLC3B (a precursor form of LC3B), LC3B (a cleaved form of proLC3B by ATG4) harboring either WT or R/Q mutant, respectively, or LC3B-G120A, which fails to conjugate with PE due to substitution of its C-terminal glycine to alanine33.