Taxonomic distribution of proteins containing LsmAD domains

The tree below includes only several representative species and genera. The complete taxonomic breakdown of all proteins containing LsmAD domains can be accessed here. Click the counts or percentage values to display the corresponding proteins.

Ataxin-2 and huntingtin interact with endophilin-A complexes to function inplastin-associated pathways.

Ralser M, Nonhoff U, Albrecht M, Lengauer T, Wanker EE, Lehrach H, Krobitsch S
Hum Mol Genet. 2005; 14: 2893-909

Spinocerebellar ataxia type 2 is an inherited neurodegenerative disorder that is caused by an expanded trinucleotide repeat in the SCA2 gene, encoding apolyglutamine stretch in the gene product ataxin-2. Although evidence has beenprovided that ataxin-2 is involved in RNA metabolism, the physiological function of ataxin-2 remains unclear. Here, we demonstrate that ataxin-2 interacts withtwo members of the endophilin family, endophilin-A1 and endophilin-A3. Toelucidate the physiological implications of these interactions, we exploitedyeast as a model system and discovered that expression of ataxin-2 as well asboth endophilin proteins is toxic for yeast lacking the SAC6 gene productfimbrin, a protein involved in actin filament organization and endocytoticprocesses. Intriguingly, expression of huntingtin, another polyglutamine protein interacting with endophilin-A3, was also toxic in Deltasac6 yeast. These effects can be suppressed by simultaneous expression of one of the two human fimbrinorthologs, L- or T-plastin. Moreover, we have discovered that ataxin-2 associateswith L- and T-plastin and that overexpression of ataxin-2 leads to accumulationof T-plastin in mammalian cells. Thus, our findings suggest an interplay between ataxin-2, endophilin proteins and huntingtin in plastin-associated cellularpathways.