Croquemort elicits activation of the immune deficiency pathway in ticks.

The immune deficiency (IMD) pathway directs host defense in arthropods upon bacterial infection. In Pancrustacea, peptidoglycan recognition proteins sense microbial moieties and initiate nuclear factor-κB-driven immune responses. Proteins that elicit the IMD pathway in non-insect arthropods remain elusive.

Binding and Functional Folding (BFF): A Physiological Framework for Studying Biomolecular Interactions and Allostery.

EF-hand Ca-binding proteins (CBPs), such as S100 proteins (S100s) and calmodulin (CaM), are signaling proteins that undergo conformational changes upon increasing intracellular Ca. Upon binding Ca, S100 proteins and CaM interact with protein targets and induce important biological responses. The Ca-binding affinity of CaM and most S100s in the absence of target is weak (K > 1 μM).

Physiologically Relevant Free Ca Ion Concentrations Regulate STRA6-Calmodulin Complex Formation via the BP2 Region of STRA6.

The interaction of calmodulin (CaM) with the receptor for retinol uptake, STRA6, involves an α-helix termed BP2 that is located on the intracellular side of this homodimeric transporter (Chen et al., 2016 [1]). In the absence of Ca, NMR data showed that a peptide derived from BP2 bound to the C-terminal lobe (C-lobe) of Mg-bound CaM (CaM).

Specificity of Molecular Fragments Binding to S100B versus S100A1 as Identified by NMR and Site Identification by Ligand Competitive Saturation (SILCS).

S100B, a biomarker of malignant melanoma, interacts with the p53 protein and diminishes its tumor suppressor function, which makes this S100 family member a promising therapeutic target for treating malignant melanoma. However, it is a challenge to design inhibitors that are specific for S100B in melanoma versus other S100-family members that are important for normal cellular activities. For example, S100A1 is most similar in sequence and structure to S100B, and this S100 protein is important for normal skeletal and cardiac muscle function.