TDP43 and hnRNP K Regulate Alternative Splicing of DNAJC5

Area of Science:

• Molecular Biology
• Neuroscience
• Genetics

Background:

• Alternative splicing is crucial for mRNA maturation and cellular function.
• Dysregulation of splicing factors, like TDP43, is implicated in neurodegenerative diseases such as ALS.
• Loss of TDP43 in ALS leads to aberrant mRNA splicing, including cryptic exon inclusion, exacerbating disease pathology.

Purpose of the Study:

• To investigate the role of TDP43 and hnRNP K in the splicing regulation of the DNAJC5 gene.
• To elucidate the mechanism by which TDP43 and hnRNP K influence DNAJC5 splicing and its downstream effects.
• To understand the implications of this regulatory network in ALS progression.

Main Methods:

• TDP43 and hnRNP K knockdown experiments in cellular models.
• RNA-binding assays to confirm TDP43 and hnRNP K interaction.
• Analysis of DNAJC5 transcript splicing patterns.
• Investigation of binding sites for TDP43 and hnRNP K on the DNAJC5 gene.

Main Results:

• TDP43 knockdown was observed to regulate DNAJC5 transcript splicing.
• hnRNP K knockdown phenocopied the splicing defects observed with TDP43 knockdown.
• TDP43 and hnRNP K were found to interact in an RNA-dependent manner.
• Canonical splicing of DNAJC5 was confirmed to be dependent on specific binding sites for TDP43 and hnRNP K within the transcript.
• The study identified TDP43 and hnRNP K as key regulators of DNAJC5 splicing.

Conclusions:

• Both TDP43 and hnRNP K play critical roles in the canonical splicing of the DNAJC5 transcript.
• The interaction between TDP43 and hnRNP K, mediated by RNA, is essential for proper DNAJC5 splicing.
• Dysregulation of TDP43 and hnRNP K impacts DNAJC5 function, affecting endosomal traffic and potentially contributing to ALS progression.