The distribution of mesenchyme proteoglycan (PG-M) during wing bud outgrowth

Abstract

This study utilizes immunofluorescence to describe the distribution of several extracellular matrix molecules in the chick embryo during the process of limb outgrowth and the formation of precartilage condensations. A large chondroitin sulfate proteoglycan (PG-M) is detected at the wing level at Hamburger and Hamilton stage 14 in and under the dorsal ectoderm, and is associated with the basement membranes around the neural tube, notochord and pronephros, but not with other basement membranes. The galactose-specific lectin, peanut agglutinin (PNA), has a similar distribution except that it also binds to the dorsal side of the neural tube. PG-M is not detected in the limb mesenchyme until after stage 17, when it is present in the distal region, as is PNA-binding material. With further development of the wing bud, PG-M is present in the subectodermal mesenchyme, the mesenchyme at the distal tip and in the prechondrogenic core. After stage 22 PNA-binding material becomes localized in the prechondrogenic core, the basement membranes under the apical ectodermal ridge, and the ventral sulcus. The distribution of these components (PG-M and PNA binding material) overlaps, but differs from that of type I collagen and fibronectin and basement membrane components, such as laminin, basement membrane heparan sulfate proteoglycan, and type IV collagen. Tenascin, on the other hand, is not detected in the limb bud until stage 25, after the appearance of cartilage matrix components such as type II collagen and cartilage proteoglycan (PG-H). These results are considered in relation to the formation of precartilage aggregates, and indicate that PNA binds to components in precartilage aggregates other than PG-M or tenascin.

Versican Mediates Mesenchymal-Epithelial Transition

“…Versican is a large chondroitin sulfate proteoglycan identified as one of the major extracellular molecules in the prechondrogenic mesenchymal condensation area (Kimata et al, 1986;Shinomura et al, 1990). Four different isoforms of versican have been found, which are determined by alternate splicing.…”

Transient Expression of PG‐M/Versican, a Large Chondroitin Sulfate Proteoglycan in Developing Chicken Retina

“…A large chondroitin sulfate proteoglycan, PG-M, was shown to be transiently expressed in the mesenchymal cell condensation areas of chicken limb buds at the prechondrogenic stages (Kimata et al, 1986;Shinomura et al, 1990). Transient expression of PG-M was also seen in various embryonic tissues during morphogenesis and differentiation (Yamagata et al, 1993), suggesting that PG-M plays some regulatory roles in these biological events.…”

Neural Tissue Co-Culture with Mesenchyme to Investigate Patterningof Peripheral Nerve During Murine Embryonic Limb Development

“…The lectin domain of versican binds tenascin (Aspberg et al 1995), increasing tenascin's anti-adhesive properties (Probstmeier et al 2000). Likewise, versican binding to other ECM molecules may block neurite adhesion to other permissive matrix substrates such as fibronectin and collagen (Yamagata et al 1989), which, along with versican, are all expressed in incipient limb cartilage tissues (Shinomura et al 1990). As reported previously (Williams et al 2005), in limb cell cultures derived from hdf homozygous mutant embryos, at either 3 or 6 days Type II collagen or versican-positive cartilage foci were not observed (Figure 5f).…”

“…The large chondroitin sulfate proteoglycan, versican, is also localized in the precartilage and early chondrogenic limb ECM Shinomura et al 1990Shinomura et al , 1995Snow et al 2005). Versican interacts with numerous matrix and cell surface proteins including CD44, hyaluronan, tenascin, fibulins, fibrillin, fibronectin, selectins, and EGF receptors LeBaron et al 1992;Aspberg et al 1995Aspberg et al , 1997Zhang et al 1998;Kawashima et al 2000;Olin et al 2001;Isogai et al 2002).…”

“…Versican interacts with numerous matrix and cell surface proteins including CD44, hyaluronan, tenascin, fibulins, fibrillin, fibronectin, selectins, and EGF receptors LeBaron et al 1992;Aspberg et al 1995Aspberg et al , 1997Zhang et al 1998;Kawashima et al 2000;Olin et al 2001;Isogai et al 2002). Its function has been linked to cartilage differentiation Shinomura et al 1990), cell proliferation (Zhang et al 1999;Yang et al 2003), and tissue patterning (Chalepakis et al 1993;Harris and Jahoda, 2001). The recent availability of the heart defect (hdf) mutant mouse (Zhang et al 1994), which bears an embryonic homozygous lethal mutation of Cspg2 encoding the core protein of versican (Mjaatvedt et al 1998), has shown that expression of the mature versican proteoglycan is pivotal to limb chondrogenesis (Williams et al 2005).…”