Striated plectin patterns are observed in ple1, ple1b, and dessamples; in ple1d and ple1d/des samples, such patterns are missing. The arrow and arrowheads in the ple1d panel represent plectin-positive sarcolemmal and interior dotlike structures, respectively. Note that the interior of ple1d/des fibers is completely devoid of plectin-positive signals. (B) Teased fibers of EDL were immunostained as in A. Note, the signal associated with longitudinal perinuclear structures was decreased in ple1 compared with ple1b fibers (arrows). Also, costameres were focally disorganized in ple1d and des samples (arrowheads). (C) Ple1d soleus sections double immunolabeled for plectin and desmin (a), desmin and mitochondria (b), or stained for SDH (c). Inset shows subsarcolemmal aggregation of mitochondria in a magnified view of the boxed area. The electron micrograph in panel d shows internal lysis of enlarged mitochondria in the subsarcolemmal region (arrows). (D) Ple1d EDL cross section double immunolabeled for desmin and synemin revealing aggregates in the interior of fibers and largely unaffected sarcolemmal regions (see also inset, a magnified view of the boxed area). (E) Immunofluorescence microscopy of teased ple1d fibers (EDL) using antibodies as indicated. In panels a and b, note the largely unaffected perinuclear and costameric patterns of plectin 1 and 1f, respectively. Panels c and c′ represent sequential confocal sections of one fiber. An optical cross section of this fiber (marked 1) is shown as an inset in panel c′, with horizontal lines indicating the positions of the planes shown in panels c and c′. Note the costameric patterns lacking aggregates in panel c and that desmin aggregates in the interior part of the fiber in panel c′ (arrow). Bars: (A; B; C, a and b; D; and E) 20 μm; (C, c) 50 μm; (C, d) 2 μm. (F) Quantitative immunoblotting of plectin in gastrocnemius lysates from different mouse mutants. Data, relative to WT samples (100%), represent the means ± SEM of three experiments.<p><b>Copyright information:</b></p><p>Taken from "Myofiber integrity depends on desmin network targeting to Z-disks and costameres via distinct plectin isoforms"</p><p></p><p>The Journal of Cell Biology 2008;181(4):667-681.</p><p>Published online 19 May 2008</p><p>PMCID:PMC2386106.</p><p></p
