eLife assessment
This valuable contribution follows past descriptions of ciliation defects, potentially linked to cholinergic neuronal dysfunction, associated with mutated G2019S Lrrk2 expression. The strength of evidence is considered solid and broadly supportive of the claims concerning well-characterized cilia changes in cholinergic neurons over time in the model; however, additional work may be required to define the specificity of the pRab12 antibody in the IHC technique, dependence on LRRK2, and clarification of the cilia phenotype in sporadic PD brains that exists (for the moment) only in a non-peer-reviewed pre-print, despite the prominence of these (preliminary) results highlighted in the abstract and text of the current manuscript. It is hoped that the authors will begin to address the feedback provided by the expert reviewers to help provide a more mechanistic basis for the audience interested in cholinergic defects associated with Parkinson's disease.