Author/Editor		Winter, Lilli; Abrahamsberg, Christina; Wiche, Gerhard
Title		Plectin isoform 1b mediates mitochondrion - intermediate fi lament network linkage and controls organelle shape
Type		članek
Vol. and No.		Letnik 181, št. 6
Publication year		2008
Volume		str. 903-911
ISSN		0021-9525 - The Journal of cell biology
Language		eng
Abstract		Plectin is a versatile intermediate filament (IF)-bound cytolinker protein with a variety of differentially spliced isoforms accounting for its multiple functions. One particular isoform, plectin 1b (P1b), remains associated with mitochondria after biochemical fractionation of fibroblasts and cells expressing exogenous P1b. Here, we determined that P1b is inserted into the outer mitochondrial membrane with the exon 1b-encoded N-terminal sequence serving as a mitochondrial targeting and anchoring signal. To study P1b-related mitochondrial functions, we generated mice that selectively lack this isoform but express all others. In primary fibroblasts and myoblasts derived from these mice, we observe a substantial elongation of mitochondrial networks, whereas other mitochondrial properties remain largely unaffected. Normal morphology of mitochondria could be restored by isoform-specific overexpression of P1b in P1b-deficient as well as plectin-null cells. We propose a model where P1b both forms a mitochondrial signaling platform and affects organelle shape and network formation by tethering mitochondria to IFs.
Keywords		plektin izoform 1b mitohondri funkcije plectin isoform 1b mitochondri functions