Two forms of the P light chain of myosin in rabbit and bovine hearts

Westwood, Sara A.; Perry, S. V.

doi:10.1016/0014-5793(82)80212-3

Cited by 27 publications

(6 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Thus, the triad pattern of variants could result from the partial superposition of two phosphorylated/non-phosphorylated pairs, which will be referred to as the hypothesis of doublets of phosphorylated/non-phosphorylated (P/non-P) pairs. Slightly different bands of rMLCs (referred to as P-light chain polymorphisms) have been observed in the ventricle of different species, including rabbit and bovine [35] and human [17], and in slow-twitch, but not in fasttwitch skeletal muscle types of the rabbit [36]. The data reported in this paper indicate that the presence of doublets of P/non-P pairs of rMLCs might be a ubiquitous feature of skeletal muscle.…”

Section: Rabbitmentioning

confidence: 64%

Protein variants of skeletal muscle regulatory myosin light chain isoforms: prevalence in mammals, generation and transitions during muscle remodelling

González

Negredo

Hernando

et al. 2002

Pflugers Arch - Eur J Physiol

View full text Add to dashboard Cite

The regulatory myosin light chains (rMLCs) of mammalian skeletal muscle display protein diversity arising from the existence of different isotypes and protein phosphorylation. Two-dimensional electrophoresis and immunoblotting allowed us to identify three variants of the slow and fast rMLC isoforms (designated LC2s, LC2s1, LC2s2, and LC2f, LC2f1, LC2f2, respectively, from less to more acidic). This study aimed to characterize their prevalence among different species and muscle types, the mechanism(s) of their generation and their transitions during fast-to-slow fibre type switching. In vitro dephosphorylation and back-phosphorylation experiments and mass spectrometric analysis of tryptic digests indicate that: (1) both acidic variants, within each isoform, contain a phosphorylated peptide, (2) all variants of each isoform share identical tryptic peptides, (3) only one phosphopeptide is present per isoform, and (4) the intermediate-acidic variants of both isoforms contain the same peptide in their phosphorylated and non-phosphorylated forms. The data indicate that the triad pattern of variants results from two partially superimposed doublets of phosphorylated/non-phosphorylated pairs. Continuous, low-frequency electrical stimulation of rat extensor digitorum longus muscle changed the relative proportions of variants within each isoform towards those of the soleus. It is suggested that the doublets of phosphorylated/non-phosphorylated pairs are involved in rMLC exchange during sarcomere remodelling.

show abstract

Section: Rabbitmentioning

confidence: 64%

Protein variants of skeletal muscle regulatory myosin light chain isoforms: prevalence in mammals, generation and transitions during muscle remodelling

González

Negredo

Hernando

et al. 2002

Pflugers Arch - Eur J Physiol

View full text Add to dashboard Cite

show abstract

“…But occasionally a faint, more acidic, third spot was also visible which is thought to represent a second type of VLC 2 (2O) . Such a second VLC 2 type has also been described in several vertebrate species beside man' 33 '. The VLC, type occurring in hypertrophic atria was variable and in all cases much reduced in comparison to its VLC 2 counterpart.…”

Section: Variation In Light Chain Complementmentioning

confidence: 85%

Myosin isoenzymes in human hypertrophic hearts. Shift in atrial myosin heavy chains and in ventricular myosin light chains

Schaub

Tuchschmid

Srihari

et al. 1984

European Heart Journal

View full text Add to dashboard Cite

show abstract

“…Two monophosphorylated LC-2 forms having the same MW but different IEP exist in the ventricle of several species (13,15,19,24,26,29) but only one form exists in the atrium (19).…”

Section: Introductionmentioning

confidence: 99%

Myosin P-light chain isoenzymes in the human heart: evidence for diphosphorylation of the atrial P-LC form

Morano

Wankerl²,

Böhm³

et al. 1989

Basic Res Cardiol

View full text Add to dashboard Cite

We studied myosin light chains (LC) of human atrium and ventricle of normal and diseased individuals by a high-resolution 2-dimensional polyacrylamide gel electrophoresis (2D-PAGE) technique. Atrial LCs (ALC-1, ALC-2 (= P-LC)) revealed both higher molecular weights and lower isoelectric points (IEP) than their ventricular counterparts (VLC-1, VLC-2 (= P-LC)). Different P-LC forms with their distinct myosin isoenzymes have been designated as P-LC-polymorphism and myosin P-LC isoenzymes, respectively. In the dephosphorylated state two VLC-2 forms (VLC-2 and VLC-2*) with the same MW and different IEP, but only one ALC-2 form, were found. In the partially phosphorylated state ALC-2 appeared to be single- and double-phosphorylated (three spots in the 2D-PAGE), whereas the two VLC-2 forms appeared to be single-phosphorylated each (four spots in the 2D-PAGE). Phosphoryl-transfer from ATP to the P-LC forms was studied using skinned fibers incubated with MLCK (myosin light chain kinase) and (gamma-32P)ATP. Ventricular myosin P-LC isoenzyme pattern was usually the same in normal and diseased patients: the VLC-2 to VLC-2* ratio was approx. 70/30, but in one patient with valvular heart disease (VHD) the relation was 55/45 (shift to the VLC-2* form). In hypertrophied atria of VHD patients a shift of the myosin P-LC isoenzyme pattern to the VLC-2* form occurred, too.

show abstract

Two forms of the P light chain of myosin in rabbit and bovine hearts

Cited by 27 publications

References 32 publications

Protein variants of skeletal muscle regulatory myosin light chain isoforms: prevalence in mammals, generation and transitions during muscle remodelling

Protein variants of skeletal muscle regulatory myosin light chain isoforms: prevalence in mammals, generation and transitions during muscle remodelling

Myosin isoenzymes in human hypertrophic hearts. Shift in atrial myosin heavy chains and in ventricular myosin light chains

Myosin P-light chain isoenzymes in the human heart: evidence for diphosphorylation of the atrial P-LC form

Contact Info

Product

Resources

About