An abietane diterpenoid is a potent activator of systemic acquired resistance.

Abietane diterpenoids are major constituents of conifer resins that have important industrial and medicinal applications. However, their function in plants is poorly understood. Here we show that dehydroabietinal (DA), an abietane diterpenoid, is an activator of systemic acquired resistance (SAR), which is an inducible defense mechanism that is activated in the distal, non-colonized, organs of a plant that has experienced a local foliar infection.

Protein-protein interactions and lens transparency.

Past studies have identified posttranslational modifications of human lens proteins occurring during cataract formation, and have also demonstrated that protein-protein interactions exist between different lens crystallins. Based upon current theories of lens transparency, these posttranslational modifications and their possible effects upon crystallin interactions may be the key to understanding why the lens is able to transmit light, and why transmission is decreased during cataractogenesis. This review will summarize current knowledge of posttranslational modifications during human cataractogenesis, and will propose their possible role in protein-protein interactions that are thought to be necessary for lens transparency.

Age-dependent association of gamma-crystallins with aged alpha-crystallins from old bovine lens.

Purpose: Previous theoretical and experimental studies have predicted that the loss of weak protein interactions between alpha- and gamma-crystallins could result in a decrease in the transparent properties of the aging lens.

Methods: alpha-Crystallins were prepared from the nucleus of old bovine lens, and gamma-crystallins were prepared from whole fetal bovine lens or from the nucleus of old bovine lens. The possible interactions of old alpha-crystallins with either old gamma-crystallins or fetal gamma-crystallins were quantitated at equilibrium using microequilibrium dialysis.

Differential binding of mutant (R116C) and wildtype alphaA crystallin to actin.

Purpose: Quantitate the interaction of mutant (R116C) and wildtype human alphaA crystallins with actin.

Methods: AlphaA crystallins, expressed in a recombinant system, were purified, followed by passage through an actin affinity column.

Results: Binding of mutant alphaA crystallin was significantly less than binding of wildtype alphaA crystallin.

Transcytotic passage of albumin through lens epithelial cells.

Purpose: To characterize the transcytotic passage of albumin through lens epithelial cells.

Methods: N/N 1003A rabbit lens epithelial cells were grown to a confluent monolayer on porous filter supports (Transwell Corning, Inc., Corning, NY).