A new simple method of detecting calcium binding proteins in a protein mixture is described. sample which might include was subjected to SDS-polyacrylamide gel electrophoresis and then electrophoretically transferred nitrocellulose membrane. The membrane incubated with 45 Ca detect as radioactive bands by autoradiography. Purified troponin-C, calmodulin, myosin DTNB light chain, parvalbumin were clearly identified this method. In the whole homogenate chicken skeletal muscle, 55K found be...

The vascular smooth muscle cells of coronary arteries are distinguished from those the proximal aorta by a number structural and functional criteria which may include an increased propensity for atherosclerotic transformation. At present, source this variation between subpopulations is uncertain. Whilst thought to be derived neural crest, origin remains uncharacterized. We have previously shown that precursors vasculature enter tubular heart on same day as epicardial mantle starts envelop...

Cellular progenitors of the coronary vasculature are believed to enter chicken heart during epicardial morphogenesis between stages 17 and 27 (days 3-5) egg incubation. To trace cells which give rise arteries in vivo, we applied retroviral cell tagging procedures analyzed clonal populations vascular smooth muscle, endothelium, connective tissue hearts post-hatch chickens. Our data provide direct proof that (i) muscle begin at stage 17, substantially after begins propulsive contractions; (ii)...

A bilateral body plan is predominant throughout the animal kingdom. Bilaterality of amniote embryos becomes recognizable as midline morphogenesis begins at gastrulation, bisecting an embryonic field into left and right sides, left–right (LR) asymmetry patterning follows. While a series laterality genes expressed after LR compartmentalization has been extensively studied, prior to initiation remained unclear. Here, through biophysical quantification in high spatial temporal resolution,...

Cardiac trabeculation is a crucial morphogenetic process by which clusters of ventricular cardiomyocytes extrude and expand into the cardiac jelly to form sheet-like projections. Although it has been suggested that trabeculae enhance contractility intra-ventricular conduction, their exact function in heart development not directly addressed. We found zebrafish erbb2 mutants, we show completely lack trabeculae, significantly compromised, with mutant hearts exhibiting decreased fractional...

ABSTRACT The rhythmic contraction of the vertebrate heart is dependent on organized propagation electrical excitation through cardiac conduction system. Because both muscleand neuron-specific genes are co-expressed in cells forming myocardial tissues, two origins, myogenic and neural, have been suggested for this specialized tissue. Using replication-defective retroviruses, encoding recombinant β-galactosidase (β-gal), we analyzed cell lineage Purkinje fibers (i.e., peripheral elements...

A common feature shared by myosin-binding proteins from a wide variety of species is the presence variable number related internal motifs homologous to either Ig C2 or fibronectin (Fn) type III repeats. Despite interest in potential function these motifs, no group has clearly demonstrated for sequences muscle, intra- extracellularly. We have completed nucleotide sequence fast isoform MyBP-C (C protein) chicken skeletal muscle. The deduced amino acid reveals seven sets and three Fn MyBP-C....

In birds and mammals, cardiac myocytes terminate mitotic activity in the neonatal period regeneration of muscle does not occur after myocardial injury adult hearts. Even embryonic myocytes, which actively proliferate vivo, quickly lose when placed cell culture. Several growth factors, including fibroblast factor (FGF), have been documented hearts some shown to influence myocyte terminal differentiation However, none these factors reactivate division postmitotic nor their vivo functions...

Abstract Cells of the precardiac mesoderm (stages 4–6) and dividing myocytes early hearts 10–15) were tagged with a replication‐incompetent retrovirus (CXL) (Mikawa et al., 1991 b) encoding bacterial β‐galactosidase (β‐gal). Two protocols used to infect cardiogenic cells. (1) Small blocks (∼50 μm 2 ) anterolateral dissected from gastrula‐stage embryos incubated in liquid medium containing retrovirus. After removal CXL, tissues dispersed into single‐cell suspensions pressure injected areas...

Cardiac pacemaker cells autonomously generate electrical impulses that initiate and maintain the rhythmic contraction of heart. Although majority heart are thought to originate from primary secondary fields, we found chick arise a discrete region mesoderm outside these fields. Shortly after gastrulation, canonical Wnts promote recruitment mesodermal within this into lineage. These findings suggest cardiac physically segregated molecularly programmed in tertiary field prior onset morphogenesis.

Abstract The cardiac pacemaking and conduction system sets maintains the rhythmic pumping action of heart. Previously, we have shown that peripheral cells network in chick (periarterial Purkinje fibers) are selected within a cardiomyogenic lineage this recruitment occurs as result paracrine cues from coronary arteries. At present, cellular derivation other elements specialized (e.g. nodes bundles central system) controversial, with some proposing evidence supports neurogenic others myogenic...

A regular heart beat is dependent on a specialized network of pacemaking and conductive cells. There has been longstanding controversy regarding the developmental origin these cardiac tissues which also manifest neural-like properties. Recently, we have shown conclusively that during chicken embryogenesis, impulse-conducting Purkinje cells are recruited from myocytes in spatial association with developing coronary arteries. Here, report cultured embryonic convert to cell phenotype after...

The heart consists of cells deriving from the cardiogenic plate and also extracardiac sources. One major contributions is given by neural crest. differentiation pathway fate crest in outflow tract have been followed over a prolonged period during septation. We studied role remodeling long-term cell tracing, markers apoptosis. pattern migrating to was investigated heterospecific chicken quail chimeras retroviral infection reporter gene LacZ stemcells. tagged move areas that are...

At least fourteen epithelial cell types of the mammalian nephron develop from metanephric mesenchyme. To distinguish whether this single embryological primordium contains a heterogenous population committed renal lines or multipotent stem cell, lac-Z gene was introduced into individual progenitors by retroviral mediated transfer. The differentiated fate lac-Z-tagged daughters derived mesenchymal cells characterized after cytodifferentiation. We found that mesenchyme can generate at three...

ABSTRACT Patterning of the bipotential retinal primordia (the optic vesicles) into neural retina and pigmented epithelium depends on its interaction with overlaying surface ectoderm. The ectoderm expresses FGFs vesicles express FGF receptors. Previous FGF-expression data in vitro analyses support hypothesis that signaling plays a significant role patterning vesicle. To test this vivo we removed ectoderm, rich source FGFs. This ablation generated retinas which cell phenotypes were co-mingled....

ABSTRACT Early in embryogenesis, precursors of the limb muscula- ture are generated somite, migrate to buds and undergo terminal differentiation. Although myogenic differentiation culture is affected by several growth factors including fibroblast factor (FGF), it remains uncertain whether migration cells vivo directly regulated such factors. To investigate roles FGF signaling regulation myogenesis both somite bud, mosaic chicken embryos were that consist somitic carrying transgenes...

ABSTRACT Myosin binding protein-C (MyBP-C), also known as C-protein, is a major constituent of the thick filaments vertebrate striated muscles. The protein, ∼130 kDa, consists series 10 globular motifs (numbered I to X) each ∼90-100 amino acids, bearing resemblance C2-set immunoglobins (Ig C2) and fibronectin type III (FnIII) motifs. Using pure preparations myosin MyBP-C, it has been demonstrated that domain MyBP-C resides within C-terminal Ig C2 motif (motif X). However, in context vivo...

Using a micro two dimensional gel electrophoretic system and silver stain method, we examined the isoform patterns of myofibrillar proteins in single muscle fibers adult chicken. Several isoforms myosin light chains, tropomyosin, troponin T, I, C were identified. Analysis pectoral, anterior latissimus dorsi, sartorius soleus revealed that contained either fast or slow form each subunits, indicating exists as 'homocomplex.' The given cell was associated with chains. however, not those chains...

ABSTRACT The rhythmic heart beat is coordinated by electrical impulses transmitted from Purkinje fibers of the cardiac conduction system. During embryogenesis, impulse-conducting cells differentiate myocytes in direct association with developing endocardium and coronary arteries, but not venous This conversion into requires a paracrine interaction blood vessels vivo, can be induced vitro exposing embryonic to endothelin-1 (ET-1), an endothelial cell-associated factor. These results suggest...

Abstract During heart development, the proepicardium (PE) gives rise to cells of epicardial epithelium, connective tissue subepicardium and myocardium, smooth muscle, endothelium, coronary arteries. The PE arises as an outgrowth pericardial serosa at embryonic day 2 (Hamburger Hamilton stage [HH] 14) chick development. Between stages HH14 HH17, multicellular villous projections extend from toward dorsal aspect lesser curvature myocardium. On reaching atrioventricular (AV) junction, spread...