Insulin-like growth factor-I (IGF-I): solution properties and NMR chemical shift assignments near physiological pH

Molecular signaling involving intrinsically disordered proteins in prostate cancer

Investigations on cellular protein interaction networks (PINs) reveal that proteins that constitute hubs in a PIN are notably enriched in Intrinsically Disordered Proteins (IDPs) compared to proteins that constitute edges, highlighting the role of IDPs in signaling pathways. Most IDPs rapidly undergo disorder-to-order transitions upon binding to their biological targets to perform their function. Conformational dynamics enables IDPs to be versatile and to interact with a broad range of interactors under normal physiological conditions where their expression is tightly modulated. IDPs are involved in many cellular processes such as cellular signaling, transcriptional regulation, and splicing; thus, their high-specificity/low-affinity interactions play crucial roles in many human diseases including cancer. Prostate cancer (PCa) is one of the leading causes of cancer-related mortality in men worldwide. Therefore, identifying molecular mechanisms of the oncogenic signaling pathways that are involved in prostate carcinogenesis is crucial. In this review, we focus on the aspects of cellular pathways leading to PCa in which IDPs exert a primary role.

Quantitative analysis of exogenous IGF-1 administration of intervertebral disc through intradiscal injection

Exogenous administration of IGF-1 has been proposed as a therapy for disc degeneration. The objectives of this study were to develop a numerical model for quantitatively analysing exogenous administration of IGF-1 into the intervertebral disc (IVD) via intradiscal injection and to investigate the effects of IGF-1 administration on distribution of glucose and oxygen in the IVD. In this study, the reversible binding reaction between IGF-1 and IGF binding proteins was incorporated into the mechano-electrochemical mixture model. The model was used to numerically analyse transport of IGF-1, glucose, oxygen and lactate in the IVD after IGF-1 administration. The enhancement of IGF-1 on lactate production was also taken into account in the theoretical model. The numerical analyses using finite element method demonstrated that the binding reactions significantly affect the time-dependent distribution of IGF-1 in the IVD. It was found that the region affected by IGF-1 was smaller and the duration of the therapeutic IGF-1 level was longer in the degenerated disc with a higher concentration of IGF binding proteins. It was also found that the IGF-1 injection can reduce glucose concentration and increase lactate accumulation (i.e., lower pH) in the IVD and these influences were regulated by the IGF-1 binding reactions. This study indicated the complexity of intradiscal administration of growth factors, which needs to be fully analysed in order to achieve a successful outcome. The new theoretical model developed in this study can serve as a powerful tool in analysing and designing the optimal treatments of growth factors for disc degeneration.

Exchange enhanced sensitivity gain for solvent-exchangeable protons in 2D 1H-15N heteronuclear correlation spectra acquired with band-selective pulses

Conformational or chemical exchange can cause significant sensitivity loss in NMR spectroscopy through resonance broadening for nuclear spins involved in these processes. While this effect may sometimes be alleviated by manipulating experimental conditions such as temperature, pH, and buffers, conditions optimal for all resonances are not always achievable. As a consequence, any means of recovering or minimizing this exchange-induced sensitivity loss is potentially of significant value in regaining information otherwise lost. We report the experimental observation of significant sensitivity gain for nuclear spins undergoing chemical exchange with solvent (water) at exchange rates ca 1-10 s(-1) in (1)H-(15)N correlation spectra of proteins acquired with band-selective pulses (the SOFAST-HMQC sequence).