Light-dependent conformational change of neoxanthin in a siphonous green alga,Codium intricatum,revealed by Raman spectroscopy

Siphonous green algae, a type of deep-sea green algae, appear olive drab and utilize blue–green light for photosynthesis. A siphonous green alga, Codium (C.) intricatum, was isolated from Okinawa prefecture in Japan, and a clonal algal culture in filamentous form was established. The major light-harvesting antenna was analogous to the trimeric LHCII found in higher plants, but the C. intricatum complex contained an unusual carbonyl carotenoid siphonaxanthin. Culture conditions were optimized to achieve high siphonaxanthin content in intact lyophilized filamentous bodies. Interestingly, the carotenoid composition was different when cultured under high irradiance: all-trans neoxanthin was accumulated in addition to the normal 9′-cis form in whole cell extract. Resonance Raman spectra of intact filamentous bodies, cultured under high- and low-light conditions, confirmed the accumulation of all-trans neoxanthin under high irradiance conditions. A plausible function of the presence of all-trans neoxanthin will be discussed in relation to the regulation against high light stress.     

UBL5 is essential for pre‐mRNA splicing and sister chromatid cohesion in human cells

UBL5 is an atypical ubiquitin‐like protein, whose function in metazoans remains largely unexplored. We show that UBL5 is required for sister chromatid cohesion maintenance in human cells. UBL5 primarily associates with spliceosomal proteins, and UBL5 depletion decreases pre‐mRNA splicing efficiency, leading to globally enhanced intron retention. Defective sister chromatid cohesion is a general consequence of dysfunctional pre‐mRNA splicing, resulting from the selective downregulation of the cohesion protection factor Sororin. As the UBL5 yeast orthologue, Hub1, also promotes spliceosome functions, our results show that UBL5 plays an evolutionary conserved role in pre‐mRNA splicing, the integrity of which is essential for the fidelity of chromosome segregation.     

Antibiotic Prophylaxis in Laparoscopic Cholecystectomy: A Randomized Controlled Trial

Background

Recent meta-analyses concluded that antibiotic prophylaxis is not warranted in low-risk laparoscopic cholecystectomy. However, most trials in the meta-analyses had a relatively small sample size and were statistically underpowered. In addition, many of the trials mentioned potential cost savings owing to the elimination of prophylactic antibiotics. However, no trial has statistically estimated the cost effectiveness. To evaluate the results of meta-analyses, we conducted a randomized controlled trial on the role of prophylactic antibiotics in low-risk laparoscopic cholecystectomy with an adequate sample size.

Methods

From March 2007 to May 2013, at the Department of Surgery, Kansai Medical University, patients who were scheduled for elective laparoscopic cholecystectomy were randomly assigned to one of two arms: those who were and were not administered prophylactic antibiotics. The primary endpoint was the occurrence of postoperative infections and secondary endpoints were postoperative hospital stay and medical costs.

Findings

During the study period, 518 patients were assigned to the Antibiotics group and 519 to the No antibiotics group. Occurrences of surgical site infections, distant infections and overall infections were significantly lower in the Antibiotics group than in the No antibiotics group (0.8 vs. 3.7%, p = 0.001, OR: 0.205 (95%CI: 0.069 to 0.606); 0.4 vs. 3.1%, p = 0.0004, OR: 0.122 (95%CI: 0.028 to 0.533); 1.2 vs. 6.7%; p<0.0001, OR: 0.162 (95%CI: 0.068 to 0.389), respectively). The postoperative hospital stay was significantly shorter in the Antibiotics group (mean, SD: 3.69±1.56 vs. 4.07±3.00; p = 0.01) and the postoperative medical costs were significantly lower in the Antibiotics group (mean, SD: $766±341 vs. 832±670; p = 0.047). Multivariable analysis showed that independent risk factors for postoperative infectious complications were no prophylactic antibiotics (p<0.0001) and age 65 or older (p = 0.006).

Conclusions

Perioperative administration of prophylactic antibiotics should be recommended in laparoscopic cholecystectomy to prevent postoperative infectious complications and to reduce medical costs.

Trial Registration

UMIN Clinical Trials Registry UMIN000003749.     

A Dimeric PINK1-containing Complex on Depolarized Mitochondria Stimulates Parkin Recruitment

Parkinsonism typified by sporadic Parkinson disease is a prevalent neurodegenerative disease. Mutations in PINK1 (PTEN-induced putative kinase 1), a mitochondrial Ser/Thr protein kinase, or PARKIN, a ubiquitin-protein ligase, cause familial parkinsonism. The accumulation and autophosphorylation of PINK1 on damaged mitochondria results in the recruitment of Parkin, which ultimately triggers quarantine and/or degradation of the damaged mitochondria by the proteasome and autophagy. However, the molecular mechanism of PINK1 in dissipation of the mitochondrial membrane potential (ΔΨm) has not been fully elucidated. Here we show by fluorescence-based techniques that the PINK1 complex formed following a decrease in ΔΨm is composed of two PINK1 molecules and is correlated with intermolecular phosphorylation of PINK1. Disruption of complex formation by the PINK1 S402A mutation weakened Parkin recruitment onto depolarized mitochondria. The most disease-relevant mutations of PINK1 inhibit the complex formation. Taken together, these results suggest that formation of the complex containing dyadic PINK1 is an important step for Parkin recruitment onto damaged mitochondria.     

Roadside monkeys: anthropogenic effects on moor macaque (Macaca maura) ranging behavior in Bantimurung Bulusaraung National Park,Sulawesi, Indonesia

Primates - A growing body of research focuses on how anthropogenic factors affect the behavior and ecology of primates and their ecosystems. Infrastructural development, such as roads, is an...     

Characterization of ubiquitin-like polypeptide acceptor protein, a novel pro-apoptotic member of the Bcl2 family.

Monoclonal nonspecific suppressor factor (MNSF) is a cytokine with antigen nonspecific suppressive activity. MNSFbeta (a subunit of MNSF) is a 14.5 kDa fusion protein consisting of a protein with 36% identity with ubiquitin and ribosomal protein S30. The ubiquitin-like segment (Ubi-L) may be cleaved from MNSFbeta in the cytosol. Recently, we have observed that Ubi-L covalently binds to intracellular proteins in mitogen-activated murine T-helper type 2 clone, D.10 cells. In this study, we purified a 33.5 kDa Ubi-L adduct from D.10 cell lysates by sequential chromatography on DEAE, anti-(Ubi-L) Ig-conjugated Sepharose, and hydroxylapatite. MALDI-TOF-MS fingerprinting revealed that this Ubi-L adduct consists of an 8.5 kDa Ubi-L and a Bcl2-like protein, murine orthologue of a previously cloned human BCL-G gene product with pro-apoptotic function. Murine Bcl-G mRNA was highly expressed in testis and significantly in spleen. In addition, the level of Bcl-G mRNA expression was increased in concanavalin A- and interferon gamma-activated D.10 cells. The 33.5 kDa Ubi-L adduct was expressed in spleen but not in testis, even though Bcl-G protein was highly expressed in this tissue. The antisense oligonucleotide to Bcl-G significantly decreased the level of the Ubi-L adduct formation in concanavalin A-activated D.10 cells and the proliferative response of the D.10 cells. These results suggest that the post-translational modification of Bcl-G by Ubi-L might be implicated in T-cell activation.