The two large cytoplasmic domains (C1 and C2) of adenylyl cyclases (AC), when expressed separately and mixed together, reconstitute enzyme activity that can be regulated by various modulators. Therefore, we have used the C1 or its C1a subdomain and C2 regions from type I AC (ACI) and type V AC (ACV) to identify the region on ACI that interacts with bg subunits of heterotrimeric G proteins. In a...

Protein Kinase D (PKD) isoenzymes regulate the formation of transport carriers from the trans-Golgi network (TGN) that are en route to the plasma membrane. The PKD C1a domain is required for the localization of PKDs at the TGN. However, the precise mechanism how PKDs are recruited to the TGN is still elusive. Here we report that ADP-ribosylation factor1 (ARF1), a small GTPase of the Ras superfa...

Translocation of protein kinase C (PKC) alpha, beta II, delta and epsilon fused to enhanced green fluorescent protein (EGFP) was studied in living neuroblastoma cells by confocal microscopy. Exposure to carbachol elicited transient translocation of PKC alpha-EGFP and beta II-EGFP in most of the cells, PKC delta-EGFP in a few cells and induced sustained translocation of PKC epsilon-EGFP. To moni...

By mutation and strain improvement techniques idiotrophs of Micromonospora purpurea, the gentamicin-producing organism, were obtained which require an exogenous source of 2-deoxystreptamine in order to produce gentamicin. Streptamine incorporation afforded a mixture of 2-hydroxygentamicin C as a complex of essentially the C1 and C2 components whereas 2-deoxystreptamine when incorporated by the ...

We consider a reaction-diffusion-advection equation with a nonlinearity of the KPP type in a cellular flow. We show that the minimal pulsating traveling front speed c∗(A) in a flow of amplitude A satisfies the upper and lower bounds C1A ≤ c∗(A) ≤ C2A for A 1. We also analyze a related eigenvalue problem and establish an “averaging along the streamlines” principle for the positive eigenfunction ...

Co-evolutionary processes in plant-pathogen/herbivore systems indicate that protease inhibitors have a particular value in biotic interactions. However, little is known about the defensive role of their targets, the plant proteases. C1A cysteine proteases are the most abundant enzymes responsible for the proteolytic activity during different processes like germination, development and senescenc...

Protein kinase C α (PKCα) is a nodal regulator in several intracellular signaling networks. PKCα is composed of modular domains that interact with each other to dynamically regulate spatial-temporal function. We find that PKCα specifically, rapidly and reversibly self-assembles in the presence of calcium in vitro. This phenomenon is dependent on, and can be modulated by an intramolecular intera...

C1A cysteine peptidases are synthesized as inactive proenzymes. Activation takes place by proteolysis cleaving off the inhibitory propeptide. The inhibitory capacity of propeptides from barley cathepsin L and B-like peptidases towards commercial and barley cathepsins has been characterized. Differences in selectivity have been found for propeptides from L-cathepsins against their cognate and no...

The hallmark for protein kinase C activation is its "translocation" to membranes following generation of lipid second messengers. This translocation is mediated by the C1 and C2 domains, two membrane-targeting modules, whose engagement on membranes provides the energy for an activating conformational change in which an autoinhibitory pseudosubstrate sequence is released from the active site. No...