My passion for cell biology is rooted in my PhD studies at Rockefeller Univesity, one of the great insitutions for the study of cell biology (http://www.rockefeller.edu/about/awards/nobel/). Although Palade, de Duve and Claude were before my time, I learned cell biology from Gunter Blobel, whose research centers on how proteins get to their target destination. As every plant biologist knows, plants offer unique challenges to the study of cell biology. Knowing the positions of proteins in time and space within the cell is just as important as knowing which proteins and mRNAs are in the cell, but not as amenable to high-throughput methods, and especially not in plant cells.
Two new papers in Plant Cell advance our understanding of proteins in time and space in plant cells.
In "Protein–Protein and Protein–Membrane Associations in the Lignin Pathway", by Bassard et al., analysis of the supramolecular organization of enzymes in the lignin pathway shows that cytochrome P450s oligomerize and move along with the very mobile plant endoplasmic reticulum. Their expression favors relocalization of their soluble partner proteins nearer the membrane and association of sequential enzymes in the pathway. (http://www.plantcell.org/content/early/2012/11/26/tpc.112.102566.full.pdf+html)
"The KEEP ON GOING Protein of Arabidopsis Regulates Intracellular Protein Trafficking and Is Degraded during Fungal Infection" by Bu and Innes shows that Arabidopsis KEEP ON GOING plays a central role in regulating movement of proteins from the plasma membrane to the central vacuole and in the secretion of defense proteins to the extracellular space. (http://www.plantcell.org/content/early/2012/11/26/tpc.112.105254.full.pdf+htm).
Almost 30 years after my first cell biology course, I still find it mind-boggling how cells manage to move so many proteins, peptides, carbohydrates and other complex molecules in and out and around, using lipid signals, the cytoskeleton, protein complexes, receptors, adaptor proteins etc.- Cells are beautiful!
Via Mary Williams