deletions | additions       diff --git a/Methods_qpcr.tex b/Methods_qpcr.tex  index 8a040c8..f2a09f0 100644  --- a/Methods_qpcr.tex  +++ b/Methods_qpcr.tex 
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Male adult flies were maintained in 4 days of 12h:12h LD cycle and following continuous dark period (DD). 120--150 fly heads were collected each time point (CT0-CT20) in second day of DD.  Total RNA was extracted using Trizol reagent (Invitrogen) and reverse transcribed using RevertAid First Strand cDNA Synthesis Kit (Thermo scientific).  Quantitative real-time  PCR was performed using TOPreal qPCR 2x premix (RT500M, Enzynomics, South Korea). Expression levels of \emph{period} gene was normalized to rp49 levels. Primer sets used: period (5'-GACCGAATCCCTGCTCAATA-3', 5'-GTGTCATTGGCGGACTTCTT-3'), rp49 (5'-ATGACCATCCGCCCAGCATA-3', 5'-GAGAACGCAGGCGACCGTTG-3')     
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