Nitrogen-dependent small RNA profiling of Arabidopsis ProAtUBQ10:AtAMT1;1-ORF transgenic plants(Rk4 Sample, from nitrogen-depleted roots in hydroponics conditions)
The constitutive expression of ammonium transporter (AMT) AtAMT1;1 under a atamt1;1-1 (ko11) mutant background of Arabidopsis thaliana showed higher transcript level in shoots under nitrogen starvation and degradation in roots. Whether the nitrogen- and organ- dependent expression of AtAMT1;1 is regulated by small RNAs remains unknown. To further investigate the potential nitrogen-dependent small RNAs, we sequenced the library constructed from roots of 6-week-old hydroponic ProAtUBQ10:AtAMT1;1 transgenic plants treated with 4-day nitrogen-depletion before harvest. Total RNA was extracted from 6-week-old hydroponic grown  transgenic plants by TRIzol reagent (Invitrogen) following the manufacturer’s instructions. Small RNA libraries were constructed using TruSeq Small RNA Sample Prep Kit (Illumina) following the manufacturer’s instructions. Gel slices corresponding to approximately 15–30 nt smRNAs were recovered and then sequenced by Illunina HiSeq2000 platform at Novogene Bioinformatics Institute.