Chasing Coiled Coils: Intermediate Filaments in Plants

The cytoskeleton's structurally most resilient components, the intermediate filaments (IFs), have attracted the interest of cell biologists for more than two decades. IFs form extensive networks in many animal cells, and are thought to provide considerable tensile strength to the cells and tissues. In fact, the term “cytoskeleton” has originally been coined for the insoluble fibrous remains of detergent extracted animal cells. Nevertheless, cells can survive quite well without an IF network, and even without the subunit proteins that build the 10 nm wide polymeric filaments. Hence, the vital function of these cytoskeletal components is still hotly debated. Against this background, it may be premature to start suggesting functions for IFs in plants. Yet this is exactly what quite a number of researchers have begun to do. Because much recent evidence supports the idea of a plant IF cytoskeleton, it seems timely to examine this evidence and discuss its impact on our current understanding of IF function.