The 3' untranslated region of human Cyclin-Dependent Kinase 5 Regulatory subunit 1 contains regulatory elements affecting transcript stability.
BACKGROUND
CDK5R1 plays a central role in neuronal migration and differentiation during central nervous system development. CDK5R1 has been implicated in neurodegenerative disorders and proposed as a candidate gene for mental retardation. The remarkable size of CDK5R1 3'-untranslated region (3'-UTR) suggests a role in post-transcriptional regulation of CDK5R1 expression.


RESULTS
The bioinformatic study shows a high conservation degree in mammals and predicts several AU-Rich Elements (AREs). The insertion of CDK5R1 3'-UTR into luciferase 3'-UTR causes a decreased luciferase activity in four transfected cell lines. We identified 3'-UTR subregions which tend to reduce the reporter gene expression, sometimes in a cell line-dependent manner. In most cases the quantitative analysis of luciferase mRNA suggests that CDK5R1 3'-UTR affects mRNA stability. A region, leading to a very strong mRNA destabilization, showed a significantly low half-life, indicating an accelerated mRNA degradation. The 3' end of the transcript, containing a class I ARE, specifically displays a stabilizing effect in neuroblastoma cell lines. We also observed the interaction of the stabilizing neuronal RNA-binding proteins ELAV with the CDK5R1 transcript in SH-SY5Y cells and identified three 3'-UTR sub-regions showing affinity for ELAV proteins.


CONCLUSIONS
Our findings evince the presence of both destabilizing and stabilizing regulatory elements in CDK5R1 3'-UTR and support the hypothesis that CDK5R1 gene expression is post-transcriptionally controlled in neurons by ELAV-mediated mechanisms. This is the first evidence of the involvement of 3'-UTR in the modulation of CDK5R1 expression. The fine tuning of CDK5R1 expression by 3'-UTR may have a role in central nervous system development and functioning, with potential implications in neurodegenerative and cognitive disorders.
Department of Biology and Genetics, Medical Faculty, University of Milan, Via Viotti 3/5, 20133 Milan, Italy. silvia.moncini@unimi.it
Silvia
S
Moncini
Annamaria
A
Bevilacqua
Marco
M
Venturin
Claudia
C
Fallini
Antonia
A
Ratti
Angelo
A
Nicolin
Paola
P
Riva
D020413:3' Untranslated Regions / Q000235:genetics / Q000378:metabolism*; D002454:Cell Differentiation / Q000235:genetics; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000235:genetics; D002490:Central Nervous System / Q000254:growth & development / Q000378:metabolism / Q000473:pathology; D051959:ELAV Proteins / Q000235:genetics / Q000378:metabolism; D005786:Gene Expression Regulation / Q000235:genetics; D006801:Humans; D008607:Intellectual Disability / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D047908:Intracellular Signaling Peptides and Proteins / Q000235:genetics; D009419:Nerve Tissue Proteins / Q000096:biosynthesis* / Q000235:genetics; D019636:Neurodegenerative Diseases / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D009474:Neurons / Q000378:metabolism* / Q000473:pathology; D020871:RNA Stability / Q000235:genetics; D019885:Sulfur Group Transferases; D024101:Mitochondrial Proteins
D020413:3' Untranslated Regions; D051959:ELAV Proteins; D047908:Intracellular Signaling Peptides and Proteins; D009419:Nerve Tissue Proteins; C405930:CDK5RAP1 protein, human; D019885:Sulfur Group Transferases; D024101:Mitochondrial Proteins