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).