Left ventricular hypertrophy (LVH) is a major risk factor for adverse cardiovascular events. Recently, a novel candidate gene encoding the
carboxypeptidase X member 2 (CPXM2) was found to be associated with
hypertension-induced LVH. CPXM2 belongs to the M14 family of metallocarboxypeptidases, yet it lacks detectable
enzyme activity, and its function remains unknown. Here, we investigated the impact of micro (mi)RNA-29b, miRNA-195, and miRNA-497 on the posttranscriptional expression control of CPXM2. Candidate
miRNAs for CPXM2 expression control were identified in silico. CPXM2 expression in rat cardiomyocytes (H9C2) was characterized via real-time PCR, Western blotting, and immunofluorescence. Direct
miRNA/target
mRNA interaction was analysed by dual
luciferase assay. CPXM2 was expressed in H9C2 and co-localised with z-disc associated
protein PDZ and LIM domain 3 (Pdlim3). Transfection of H9C2 with miRNA-29b, miRNA-195, and miRNA-497 led to decreased levels of CPXM2
mRNA and
protein, respectively. Results of dual
luciferase assays revealed that miRNA-29b and miRNA-497, but not miRNA-195, directly regulated CPXM2 expression on a posttranscriptional level via binding to the
3'UTR of CPXM2
mRNA. We identified two
miRNAs capable of the direct posttranscriptional expression control of CPXM2 expression in rat cardiomyocytes. This novel data may help to shed more light on the-so far-widely unexplored expression control of CPXM2 and its potential role in LVH.