Integral plasma membrane proteins detected by MS and their relative abundance in leaf and root tissue (q-value).

Proteins are grouped according to function and all annotation is via the database TAIR.
aPredicted transmembrane domains determined by Phobius (Kall et al., 2004).
bNumber of unique peptides first identified by MS/MS and then detected in reliable 14N/15N spectra used for determination of the q-value for that specific protein. All these spectra have fulfilled all criteria for that specific peptide/protein, including correct position of the protein on the SDS-gel, consistent elution of the peptide in the nano-LC gradient, and correct peptide molecular mass as well as isotopic pattern.
cThe q-value is a measure of the distribution of the peptide between root and leaf plasma membranes: A q-value of 1 means that the peptide is found in roots only; 0, in leaves only. SD is the standard deviation for the q-value of the protein based on all unique peptides for that specific protein.
dNumber of MS spectra containing reliable data for the 14N/15N peptide pair(s) used to determine the q-value.
eGenevestigator data for mRNA distribution between Arabidopsis leaf rosettes and roots converted to a simple letter code: L, mRNA found in leaves only, R, in roots only; LR, about equally distributed between leaves and roots; Lr, mainly in leaves; lR, mainly in roots.
*The three q-values for SYP71 were obtained with two unique peptides found in three neighboring segments of the SDS gel (see text for discussion).