Identification and Characterization of YME1L1, a Novel Paraplegin-Related Gene

A gene responsible for an autosomal recessive form of hereditary spastic paraplegia (SPG7) was recently identified. This gene encodes paraplegin, a mitochondrial protein highly homologous to the yeast mitochondrial AAA proteases Afg3p, Rca1p, and Yme1p, which have both proteolytic and chaperone-like activities at the inner mitochondrial membrane. By screening the expressed sequence tag database, we identified and characterized a novel human gene, YME1L1 (YME1L1-like1, HGMW-approved symbol). This gene encodes a predicted protein of 716 amino acids highly similar to all mitochondrial AAA proteases and in particular to yeast Yme1p. Expression and immunofluorescence studies revealed that YME1L1 and paraplegin share a similar expression pattern and the same subcellular localization in the mitochondrial compartment. YME1L1 may represent a candidate gene for other forms of hereditary spastic paraplegia and possibly for other neurodegenerative disorders.