In this issue

AbstractWe try harderpp. 940–952In the 60s and 70s Avis Rent‐a‐car was in second place in the car rental market, despite the fact that they were first to rent cars at major airports. Being in second place, according to their advertisements, meant that they had to try harder to satisfy their customers. It seems that those researchers who work on colorectal carcinoma (the number 2 killer cancer, number 1 in Western world frequency) are taking the same approach ‐ trying harder to find metastasis and tumor staging markers for drug development. Luque‐Garcia et al. report here on how they approached the problem with two closely related cell lines, one an aggressively metastasizing line, the other a rare metastasizer, and mass isotope affinity labeling of membrane fractions of the cells. Comparing the proteins of the two lines revealed details of the mechanism of the tumor growth and potential markers magnified imageTrx is not for kidspp. 987–1001Trix, a heavily sweetened breakfast cereal had “problems” with adults eating it before the obnoxious kids got to it in the advertisements. Trx should not have that problem. It is a family of thioredoxins conserved throughout plant and animal history. It has a number of roles, of particular interest are regulatory functions involving oxidation and reduction of disulfides in the luminal region of chloroplasts. In this article, Hall et al. explore the regulatory interactions of proteins of the thylakoid lumen with various Trx family members. Using proteomic and affinity chromatographic techniques, they identify 19 proteins that interact with thioredoxins in the chloroplast lumen. These target proteins account for more than 40% of the known luminal chloroplast proteome but virtually nothing is known about their function. magnified imageYou watch my spinal cord, I'll watch yourspp. 1050–1062Understanding the composition and function of the proteome of the spinal cord is critical to our understanding of the etiology of multiple sclerosis. Using two inbred laboratory strains of mice with different degrees of susceptibility to the experimental autoimmune encephalomyelitis (EAE), a mouse model for MS, Mikkat et al. applied proteome tools to spinal cord extracts. They built a map showing 304 different spots. Using 2‐D DIGE and MALDI‐MS they found 26 qualitatively polymorphic proteins. Of those, 14 were single amino acid substitutions, confirmed by DNA sequencing. Much of the diversity can be found in the phosphopeptides of the C‐terminal domain of the neurofilament heavy polypeptide. Further work is required to analyze the functional differences resulting from the peptide sequence variations and differences in type and number of posttranslational modifications. magnified image