Versican is a member of the group of aggregating proteoglycans involved in matrix assembly and structure and in cell adhesion. We examined changes in the distribution of versican in mammalian skin, with emphasis on hair follicle development and cycling. In adult human skin, immunostaining for versican appeared predominantly in the dermis, with intense staining of the reticular dermis. Weak staining was observed at the dermoepidermal junction and the connective tissue sheath of hair follicles. Versican expression was also noted in the reticular dermis of rat skin, within dermal papillae, and possibly associated with follicle basement membranes. During mouse hair follicle development, versican was not expressed until the hair follicles were beginning to produce fibers. With follicle maturation, versican expression intensified in the dermal papillae, reaching a maximum at the height of the growth phase (anagen), after which it diminished as the end of this phase approached. Versican immunoreactivity in the papillae decreased further during catagen and was absent from these structures during telogen. However, intense staining for versican was then observed in the neck regions of telogen follicles. As the follicles entered the next hair cycle, versican disappeared from the necks and was again seen in the dermal papillae when follicles began producing fibers. This type of expression continued throughout subsequent hair cycles and is unlike any other dermal papilla component. The results of this study are consistent with a distinct supportive role for versican in the follicle matrices during hair follicle morphogenesis and cycling.

A distinction between sulfur-rich and sulfur-poor endosperm proteins is proposed on the basis of analyses of sulfur-deficient grain, of grain proteins labelled with 35S, and of heat-denatured proteins. Grain proteins from five wheat varieties, grown in pots with excess, normal or minimal supplies of sulfur, were examined by gradient gel and sodium dodecyl sulfate electrophoresis. Restriction of sulfur altered the proportions of proteins within and between protein classes. In particular, the proportion of the low-mobility gliadins (proposed as low-S) increased at the expense of the high- mobility gliadins. In addition, the low-S grain was severely depleted in all essential amino acids, though arginine and aspartic acid increased considerably compared to normal grain. Autoradiography following electrophoresis showed that the low-mobility gliadins contained no 35S whereas the high-mobility gliadins were well labelled. A further distinction between the two groups of gliadins was provided by heating a slurry of wholemeal at 130°C for 30 min: the low-mobility gliadin components were still readily extractable with 6% urea solution but the remaining gliadins (proposed as sulfur-rich) were not.

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