In cells, biosynthetic machinery coordinates protein synthesis and folding to optimize efficiency and minimize off-pathway outcomes. However, it has been difficult to delineate experimentally the mechanisms responsible. Using fluorescence resonance energy transfer, we studied cotranslational folding of the first nucleotide-binding domain from the cystic fibrosis transmembrane conductance regulator. During synthesis, folding occurred discretely via sequential compaction of N-terminal, α-helical, and α/β-core subdomains. Moreover, the timing of these events was critical; premature α-subdomain folding prevented subsequent core formation. This process was facilitated by modulating intrinsic folding propensity in three distinct ways: delaying α-subdomain compaction, facilitating β-strand intercalation, and optimizing translation kinetics via codon usage. Thus, de novo folding is translationally tuned by an integrated cellular response that shapes the cotranslational folding landscape at critical stages of synthesis.

BackgroundThe association between C‐reactive protein (CRP) level, symptoms, and activities of daily living (ADL) in advanced cancer patients is unclear.MethodsSecondary data analysis of a multicenter prospective cohort study consisted of 2426 advanced cancer patients referred to palliative care settings was conducted to examine the cross‐sectional relationships between CRP level, symptoms, and ADL disabilities. Laboratory data, symptoms, ADL, and manual muscle testing (MMT) results were obtained at baseline. Participants were divided into four groups: low (CRP < 1 mg/dl), moderate (1 = < CRP <5 mg/dl), high (5 = < CRP < 10 mg/dl), and very high CRP (10 mg/dl = < CRP). The proportions of eight symptoms, five ADL disabilities, and three categories of MMT according to the CRP groups were tested by chi‐square tests. Multiple‐adjusted odd ratios (ORs) were calculated by using ordinal logistic regression after adjustment for age, gender, site of primary cancer, metastatic disease, performance status, chemotherapy, and setting of care.ResultsA total of 1702 patients were analysed. Positive rates of symptoms and ADL disabilities increased with increasing CRP level. In the very high‐CRP group, rates of positivity for anorexia, fatigue, and weight loss were 89.8%, 81.0%, and 79.2%, respectively, and over 70% of patients received assistance for bathing, dressing, going to the toilet, and transfer. The grade of MMT also deteriorated with increasing CRP level. Adjusted ORs for the accumulated symptoms significantly increased with increasing CRP level in the moderate‐CRP, high‐CRP, and very high‐CRP groups [1.6 (95% confidence interval 1.2–2.0), P < 0.001; 2.5 (1.9–3.2), P < 0.001; 3.5 (2.7–4.6), P < 0.001, respectively]. Adjusted ORs for the accumulated ADL disabilities significantly increased in the very high‐CRP groups [2.1 (1.5–2.9), P < 0.001].ConclusionsAssociations between CRP level, symptoms, and ADL were observed in advanced cancer patients receiving palliative care.

Physicians tend to overestimate when predicting survival in all palliative care patients, including those receiving chemotherapy.

The simplified PPI showed essentially the same predictive value as the original PPI and is an alternative when clinicians have difficulties in diagnosing delirium.

Protein misfolding causes a wide spectrum of human disease, and therapies that target misfolding are transforming the clinical care of cystic fibrosis. Despite this success, however, very little is known about how disease-causing mutations affect the de novo folding landscape. Here we show that inherited, disease-causing mutations located within the first nucleotide-binding domain (NBD1) of the cystic fibrosis transmembrane conductance regulator (CFTR) have distinct effects on nascent polypeptides. Two of these mutations (A455E and L558S) delay compaction of the nascent NBD1 during a critical window of synthesis. The observed folding defect is highly dependent on nascent chain length as well as its attachment to the ribosome. Moreover, restoration of the NBD1 cotranslational folding defect by second site suppressor mutations also partially restores folding of full-length CFTR. These findings demonstrate that nascent folding intermediates can play an important role in disease pathogenesis and thus provide potential targets for pharmacological correction.

In predicting the prognosis of patients with advanced cancer, the PS-PPI was as accurate as the PPI. The PS-PPI was useful for short- and long-term survival prediction and for the prediction of survival for patients undergoing chemotherapy. Cancer 2017;123:1442-1452. © 2016 American Cancer Society.

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Calmodulin (CaM), a physiologically important Ca(2+)-binding protein, participates in numerous cellular regulatory processes. It is dumbbell shaped and contains two globular domains connected by a short alpha-helix. Each of the globular domains has two Ca(2+)-binding sites, the EF hands. CaM undergoes a conformational change upon binding to Ca(2+), which enables it to bind to specific proteins for specific responses. Here, we successfully photocontrolled CaM binding to its target peptide using the photochromic compound N-(4-phenylazophenyl) maleimide (PAM), which reversibly undergoes cis-trans isomerization upon ultraviolet (UV) and visible (VIS) light irradiation. In order to specifically incorporate PAM, CaM mutants having reactive cysteine residues in the functional region were prepared; PAM was stoichiometrically incorporated into the cysteine residues in these mutants. Further, we prepared the target peptide, M13, fused with yellow fluorescent protein (YFP) to monitor the CaM-M13 peptide interaction. The binding of the PAM-CaM mutants, N60C, D64C and M124C, to M13-YFP was reversibly photocontrolled upon UV-VIS light irradiation at appropriate Ca(2+) concentrations.