*3.3. RNA Extraction and Reverse Transcription-Quantitative PCR (RT-qPCR) Analysis*

Total RNA was extracted from 2-cm lamina joint segments or other tissues using the MG Total RNA Extraction Kit (Macrogen, Seoul, Republic of Korea) according to the manufacturer's instructions. First-strand cDNAs were synthesized from 2 μg of total RNA using oligo(dT)15 primers and M-MLV reverse transcriptase (Promega, USA). The relative transcript levels of each gene were measured by quantitative PCR (qPCR) using gene-specific primers, and rice *Ubiquitin5* (*UBQ5*) was used as an internal control (Table S1) [90]. GoTaq qPCR Master Mix (Promega, USA) was used in a 20 μl total reaction volume, and quantitative PCR was performed using a LightCycler 480 (Roche, Switzerland). qPCR conditions were 95 ◦C for 2 min, and then 45 cycles of 95 ◦C for 10 s and 60 ◦C for 1 min.
