Deviant mass shift of hydrated product ions from sodiated beta-anilinodidrochalcones using an ion-trap mass spectrometer.

The fragmentation reactions of sodiated beta-anilinodidrochalcones have been investigated by electrospray ionization multi-stage mass spectrometry (ESI-MS(n)). The fragment ion of sodiated N-benzylidenebenzenamine (P1) easily undergoes ion-molecule reactions with the residual ESI solvent molecules (H2O and CH3OH) in the vacuum system, as verified by MS3 and accurate MS analysis. The formed hydrated ions appear as an unusual leading peak in the profile spectrum, which results in a deviant decreasing mass shift of almost 1 Da.

Validation of reference genes for real-time quantitative PCR normalisation in non-heading Chinese cabbage.

Non-heading Chinese cabbage is an important vegetable crop that includes pak choi, caixin and several Japanese vegetables like mizuna, mibuna and komatsuna. Gene expression studies are frequently used to unravel the genetics of complex traits and in such studies the proper selection of reference genes for normalisation is crucial. We assessed the expression of 13 candidate reference genes including ACTIN, ACTIN-1, ACTIN-2, GAPDH, Tub_α, CyP, EF1-α, 18S rRNA, UBQ, UBC30, PPR, PP2A and MDH.