Birc5 and Nudc are screened as candidate reference genes for RT-qPCR studies in mouse cementoblast mineralization using time-series RNA-seq data.

Background: The robustness and credibility of RT-qPCR results are critically dependent on the selection of suitable reference genes. However, the mineralization of the extracellular matrix can alter the intracellular tension and energy metabolism within cells, potentially impacting the expression of traditional reference genes, namely Actb and Gapdh.

Objective: To methodically identify appropriate reference genes for research focused on mouse cementoblast mineralization.

Materials And Methods: Time-series transcriptomic data of mouse cementoblast mineralization were used. To ensure expression stability and medium to high expression levels, three specific criteria were applied to select potential reference genes. The expression stability of these genes was ranked based on the DI index (1/coefficient of variation) to identify the top six potential reference genes. RT-qPCR validation was performed on these top six candidates, comparing their performance against six previously used reference genes (Rpl22, Ppib, Gusb, Rplp0, Actb, and Gapdh). Cq values of these 12 genes were analyzed by RefFinder to get a stability ranking.

Results: A total of 4418 (12.27%) genes met the selection criteria. Among them, Rab5if, Chmp4b, Birc5, Pea15a, Nudc, Supt4a were identified as candidate reference genes. RefFinder analyses revealed that two candidates (Birc5 and Nudc) exhibited superior performance compared to previously used reference genes.

Limitations: RefFinder's stability ranking does not consider the influence of primer efficiency.

Conclusions And Implications: We propose Birc5 and Nudc as candidate reference genes for RT-qPCR studies investigating mouse cementoblast mineralization and cementum repair.