Response characteristics of the membrane integrity and physiological activities of the mutant strain Y217 under exogenous butanol stress.

Butanol inhibits bacterial activity by destroying the cell membrane of Clostridium acetobutylicum strains and altering functionality. Butanol toxicity also results in destruction of the phosphoenolpyruvate-carbohydrate phosphotransferase system (PTS), thereby preventing glucose transport and phosphorylation and inhibiting transmembrane transport and assimilation of sugars, amino acids, and other nutrients. In this study, based on the addition of exogenous butanol, the tangible macro indicators of changes in the carbon ion beam irradiation-mutant Y217 morphology were observed using scanning electron microscopy (SEM). The mutant has lower microbial adhesion to hydrocarbon (MATH) value than C. acetobutylicum ATCC 824 strain. FDA fluorescence intensity and conductivity studies demonstrated the intrinsically low membrane permeability of the mutant membrane, with membrane potential remaining relatively stable. Monounsaturated FAs (MUFAs) accounted for 35.17% of the mutant membrane, and the saturated fatty acids (SFA)/unsaturated fatty acids (UFA) ratio in the mutant cell membrane was 1.65. In addition, we conducted DNA-level analysis of the mutant strain Y217. Expectedly, through screening, we found gene mutant sites encoding membrane-related functions in the mutant, including ATP-binding cassette (ABC) transporter-related genes, predicted membrane proteins, and the PTS transport system. It is noteworthy that an unreported predicted membrane protein (CAC 3309) may be related to changes in mutant cell membrane properties. KEY POINTS: • Mutant Y217 exhibited better membrane integrity and permeability. • Mutant Y217 was more resistant to butanol toxicity. • Some membrane-related genes of mutant Y217 were mutated.

NFAT5 up-regulates expression of the kidney-specific ubiquitin ligase gene Rnf183 under hypertonic conditions in inner-medullary collecting duct cells.

We previously reported that among the 37 RING finger protein (RNF) family members, RNF183 mRNA is specifically expressed in the kidney under normal conditions. However, the mechanism supporting its kidney-specific expression pattern remains unclear. In this study, we elucidated the mechanism of the transcriptional activation of murine Rnf183 in inner-medullary collecting duct cells. Experiments with anti-RNF183 antibody revealed that RNF183 is predominantly expressed in the renal medulla. Among the 37 RNF family members, Rnf183 mRNA expression was specifically increased in hypertonic conditions, a hallmark of the renal medulla. RNF183 up-regulation was consistent with the activation of nuclear factor of activated T cells 5 (NFAT5), a transcription factor essential for adaptation to hypertonic conditions. Accordingly, siRNA-mediated knockdown of NFAT5 down-regulated RNF183 expression. Furthermore, the -3,466 to -3,136-bp region upstream of the mouse Rnf183 promoter containing the NFAT5-binding motif is conserved among mammals. A luciferase-based reporter vector containing the NFAT5-binding site was activated in response to hypertonic stress, but was inhibited by a mutation at the NFAT5-binding site. ChIP assays revealed that the binding of NFAT5 to this DNA site is enhanced by hypertonic stress. Of note, siRNA-mediated RNF183 knockdown increased hypertonicity-induced caspase-3 activation and decreased viability of mIMCD-3 cells. These results indicate that (i) RNF183 is predominantly expressed in the normal renal medulla, (ii) NFAT5 stimulates transcriptional activation of Rnf183 by binding to its cognate binding motif in the Rnf183 promoter, and (iii) RNF183 protects renal medullary cells from hypertonicity-induced apoptosis.

Short-Term Outcomes of Open Reduction and Internal Fixation for Sanders Type III Calcaneal Fractures With and Without Bone Grafts.

Calcaneal fractures, often caused by a fall from a height, are the most common injuries encountered by orthopedic surgeons. Currently, open anatomic reduction and internal fixation (ORIF) is considered a valuable treatment of displaced intraarticular fractures of the calcaneus; however, the need for bone grafting in the treatment is still controversial. Therefore, in the present study, we investigated the outcomes of 2 methods (with and without bone grafting) used for the surgical treatment of Sanders type III calcaneal fractures. From January 2013 to September 2015, 57 cases (55 patients) with displaced Sanders type III calcaneal fractures (53 unilateral and 2 bilateral) were enrolled. The patients were divided into 2 groups: group I was treated by ORIF with bone grafting (n = 28) and group II was treated by ORIF without bone grafting (n = 29). The radiologic evaluation included Böhler's angle, Gissane's angle, and the height and width of the calcaneum. In addition, the American Orthopaedic Foot and Ankle Society questionnaires and visual analog scale were completed by the patients. During the follow-up period, no differences were found in the outcome measures (Böhler's angle, p = .447; Gissane's angle, p = .599; calcaneal height, p = .065; calcaneal width p = .077; and American Orthopaedic Foot and Ankle Society questionnaires, p = .282) with or without bone grafting. The only difference between the 2 groups was the occurrence of postoperative pain (p = .024 and p = ≤ .05), which was greater in the patients who had undergone bone grafting. We have provided evidence that bone grafting with internal fixation in the treatment of intraarticular calcaneal fractures failed to improve the restoration of Böhler's angle or Gissane's angle. No statistically significant difference was found in the short-term outcomes between the 2 methods used for the surgical treatment of Sanders type III calcaneal fractures.

[Influence of Nasal Disinfection on Nasal Bacterial Colonization through the Transsphenoidal Approach].

Objective To explore the influence of the iodine disinfection on nasal bacterial colonization through the transsphenoidal approach. Methods Totally 133 pituitary adenoma patients who underwent transsphenoidal surgery in our department from January to August 2017 were enrolled in this study. Before disinfection,pharyngeal swabs of inferior turbinate root secretions were taken for bacterial culture. After iodine disinfection,pharyngeal swabs were taken again at the same site. Changes in the nasal bacterial spectrum before and after disinfection were compared. Patients were followed up for three months after the surgery,during which any intracranial infection/bacteraemia was recorded,and its correlation with nasal bacteria colonization was analyzed. Results Nasal bacterial colonization was detected in 45 (33.8%) of 133 patients before iodine disinfection and in only 6 cases (4.5%) after iodine disinfection (χ2=34.5,P=0.000). Thus,iodine disinfection eliminated 86.7%(39/45) of the colonized bacteria. The most common nasal bacterium was Staphylococcus aureus (24.4%,11/45),followed by Klebsiella pneumoniae (24.4%,11/45),and Staphylococcus epidermidis (13.3%,6/45). One patient had high fever and chills 2 days after surgery,but blood culture and cerebrospinal fluid culture showed negative Results . After the administration of third-generation cephalosporins,the symptoms disappeared after two days. Conclusion sThere are colonized bacteria in nasal cavity. Iodine disinfection of nasal cavity can effectively clear most of the nasal bacteria. The possibility of intracranial infection/bacteremia after transsphenoidal approach is low.

The hmsT 3' untranslated region mediates c-di-GMP metabolism and biofilm formation in Yersinia pestis.

Yersinia pestis, the cause of plague, forms a biofilm in the proventriculus of its flea vector to enhance transmission. Biofilm formation in Y. pestis is regulated by the intracellular levels of cyclic diguanylate (c-di-GMP). In this study, we investigated the role of the 3' untranslated region (3'UTR) in hmsT mRNA, a transcript that encodes a diguanylate cyclase that stimulates biofilm formation in Y. pestis by synthesizing the second messenger c-di-GMP. Deletion of the 3'UTR increased the half-life of hmsT mRNA, thereby upregulating c-di-GMP levels and biofilm formation. Our findings indicate that multiple regulatory sequences might be present in the hmsT 3'UTR that function together to mediate mRNA turnover. We also found that polynucleotide phosphorylase is partially responsible for hmsT 3'UTR-mediated mRNA decay. In addition, the hmsT 3'UTR strongly repressed gene expression at 37°C and 26°C, but affected gene expression only slightly at 21°C. Our findings suggest that the 3'UTR might be involved in precise and rapid regulation of hmsT expression, allowing Y. pestis to fine-tune c-di-GMP synthesis and consequently regulate biofilm production to adapt to the changing host environment.

CRISPR-Cas12a-Assisted Recombineering in Bacteria.

Clustered regularly interspaced short palindromic repeat (CRISPR)-Cas12a (Cpf1) has emerged as an effective genome editing tool in many organisms. Here, we developed and optimized a CRISPR-Cas12a-assisted recombineering system to facilitate genetic manipulation in bacteria. Using this system, point mutations, deletions, insertions, and gene replacements can be easily generated on the chromosome or native plasmids in Escherichia coli, Yersinia pestis, and Mycobacterium smegmatis Because CRISPR-Cas12a-assisted recombineering does not require introduction of an antibiotic resistance gene into the chromosome to select for recombinants, it is an efficient approach for generating markerless and scarless mutations in bacteria.IMPORTANCE The CRISPR-Cas9 system has been widely used to facilitate genome editing in many bacteria. CRISPR-Cas12a (Cpf1), a new type of CRISPR-Cas system, allows efficient genome editing in bacteria when combined with recombineering. Cas12a and Cas9 recognize different target sites, which allows for more precise selection of the cleavage target and introduction of the desired mutation. In addition, CRISPR-Cas12a-assisted recombineering can be used for genetic manipulation of plasmids and plasmid curing. Finally, Cas12a-assisted recombineering in the generation of point mutations, deletions, insertions, and replacements in bacteria has been systematically analyzed. Taken together, our findings will guide efficient Cas12a-mediated genome editing in bacteria.

[Association of GH and IGF-1 Burden with Cardiac Structural and Functional Changes in Acromegaly Patients].

OBJECTIVES: To investigate the association of growth hormone (GH) and insulin-like growth factor (IGF-1) burden with the cardiac structural and functional changes in acromegaly patients. METHODS: Ninety-nine acromegaly patients were enrolled in this study. According to the normal range of echocardiographic parameters of Peking Union Medical College Hospital, the patients were divided into parameter normal group and abnormal group. Correlation analyses were conducted between duration of disease, mean GH, mean IGF-1, GH burden, IGF-1 burden and echocardiography data retrospectively. RESULTS: Forty eight cases (48.5%) was diagnosed as abnormal echocardiography, including enlargement of the cardiac cambers (29.3%), valvular diseases (15.1%), dilation of aortic root (5.1%), functional abnormal of left ventricle (19.2%) and wall motion abnormalities (1.0%). The average GH and IGF-1 burdens in echocardiography abnormal group (n=48) were higher than those in the normal group (n=51), without statistical significant except for the left ventricle end-systolic diameter (LVESD) (P=0.018) in GH burden comparison and E/A (P=0.011) and left atrium longitudinal dimension (LALD) (P=0.017) in IGF-1 burden comparison. Abnormal diastolic function group (n=18) had similar GH burden with the normal group (n=81) (P=0.419), but had higher IGF-1 burden than the normal group did (P=0.018).The GH burden correlated with left ventricle end-diastolic diameter (LVEDD) and LVESD, and the IGF-1 burden correlated with left ventricular ejection fraction (LVEF) , LALD, right ventricle longitudinal dimension( RVLD), Left ventricular posterior wall thickness (LVPWT), LVEDD, LVESD, and E/A ratio statistical significantlly (P<0.05). CONCLUSIONS: There exist associations of GH and IGF-1 burden with echocardiography abnormalities and cardiac complications.

Effect of Transsphenoidal Adenectomy on Glucose Tolerance Status in Patients with Growth Hormone-secreting Pituitary Adenoma.

OBJECTIVE: To explore the effect of transsphenoidal adenectomy on glucose tolerance status in patients with growth hormone (GH)-secreting pituitary adenoma. METHODS: The clinical data of 105 patients with GH-secreting pituitary adenoma who underwent transsphenoidal adenectomy in our department in 2013 were retrospectively analyzed. The glucose tolerance status, GH level, and insulin-like growth factor-1 (IGF-1) level before and after surgery were compared. RESULTS: Among these 105 patients, the blood glucose tolerance status included normal glucose tolerance (NGT) in 47 cases (44.8%), early carbohydrate metabolism disorders (ECMDs) in 26 cases (24.8%), and diabetes mellitus (DM) in 32 cases (30.5%) before surgery. After the surgery, the fasting blood glucose (P=0.006, P=0.017) and postprandial blood glucose (P=0.000, P=0.000) in the ECMDs and DM groups were significantly improved. Also, the random GH (P=0.001, P=0.004, P=0.001), nadir GH (P=0.000, P=0.001, P=0.001), and IGF-1 (P=0.005, P=0.000, P=0.000) significantly decreased during the follow-up period in NGT, ECMDs and DM groups. Compared with ECMDs and DM groups, the decrease in fasting blood glucose (P=0.029, P=0.000), postprandial blood glucose (P=0.003, P=0.000), and serum IGF-1 (P=0.048, P=0.000) were more significant in DM group. CONCLUSIONS: Transsphenoidal adenectomy can improve the blood glucose, GH, and IGF-1 levels in patients with growth hormone-secreting pituitary adenoma. Meanwhile,the surgery has a better effect in improving the glucose tolerance status and IGF-1 in patients with preoperatively confirmed DM.

HmsC, a periplasmic protein, controls biofilm formation via repression of HmsD, a diguanylate cyclase in Yersinia pestis.

Yersinia pestis, the cause of plague, forms a biofilm in the foregut of its flea vector to enhance transmission. Biofilm formation in Y. pestis is controlled by the intracellular levels of the second messenger molecule cyclic diguanylate (c-di-GMP). HmsT and Y3730, the two diguanylate cyclases (DGC) in Y. pestis, are responsible for the synthesis of c-di-GMP. Y3730, which we name here as HmsD, has little effect on in vitro biofilms, but has a major effect on biofilm formation in the flea. The mechanism by which HmsD plays differential roles in vivo and in vitro is not understood. In this study, we show that hmsD is part of a three-gene operon (y3729-31), which we designate as hmsCDE. Deletion of hmsC resulted in increased, hmsD-dependent biofilm formation, while deletion or overexpression of hmsE did not affect biofilm formation. Localization experiments suggest that HmsC resides in the periplasmic space. In addition, we provide evidence that HmsC might interact directly with the periplasmic domain of HmsD and cause the proteolysis of HmsD. We propose that HmsC senses the environmental signals, which in turn regulates HmsD, and controls the c-di-GMP synthesis and biofilm formation in Y. pestis.

Surgical management of pituitary adenoma during pregnancy.

BACKGROUND: Although conservative treatment is typically recommended for pregnant patients with pituitary adenoma (PA), surgical treatment is occasionally necessary for those with acute symptoms. Currently, surgical interventions utilized among these patients is poorly studied. AIM: To evaluate the surgical indications, timing, perioperative precautions and postoperative complications of PAs during pregnancy and to provide comprehensive guidance. METHODS: Six patients with PAs who underwent surgical treatment during pregnancy at Peking Union Medical College Hospital between January 1990 and June 2021 were recruited for this study. Another 35 pregnant patients who were profiled in the literature were included in our analysis. RESULTS: The 41 enrolled patients had acute symptoms including visual field defects, severe headaches or vision loss that required emergency pituitary surgeries. PA apoplexies were found in 23 patients. The majority of patients (55.9%) underwent surgery in the second trimester of pregnancy. A multidisciplinary team was involved in patient care from the preoperative period through the postpartum period. With the exception of 1 patient who underwent an induced abortion and 1 fetus that died due to a nuchal cord, 39 patients delivered successfully. Among them, 37 fetuses were healthy until the most recent follow-up. CONCLUSION: PA surgery during pregnancy is effective and safe during the second and third trimesters. Pregnant patients requiring emergency PA surgery require multidisciplinary evaluation and healthcare management.

A frameshift in Yersinia pestis rcsD alters canonical Rcs signalling to preserve flea-mammal plague transmission cycles.

Multiple genetic changes in the enteric pathogen Yersinia pseudotuberculosis have driven the emergence of Yesinia pestis, the arthropod-borne, etiological agent of plague. These include developing the capacity for biofilm-dependent blockage of the flea foregut to enable transmission by flea bite. Previously, we showed that pseudogenization of rcsA, encoding a component of the Rcs signalling pathway, is an important evolutionary step facilitating Y. pestis flea-borne transmission. Additionally, rcsD, another important gene in the Rcs system, harbours a frameshift mutation. Here, we demonstrated that this rcsD mutation resulted in production of a small protein composing the C-terminal RcsD histidine-phosphotransferase domain (designated RcsD-Hpt) and full-length RcsD. Genetic analysis revealed that the rcsD frameshift mutation followed the emergence of rcsA pseudogenization. It further altered the canonical Rcs phosphorylation signal cascade, fine-tuning biofilm production to be conducive with retention of the pgm locus in modern lineages of Y. pestis. Taken together, our findings suggest that a frameshift mutation in rcsD is an important evolutionary step that fine-tuned biofilm production to ensure perpetuation of flea-mammal plague transmission cycles.

Yersinia pestis, the agent responsible for the plague, emerged 6,000 to 7,000 years ago from Yersinia pseudotuberculosis, another type of bacteria which still exists today. Although they are highly similar genetically, these two species are strikingly different. While Y. pseudotuberculosis spreads via food and water and causes mild stomach distress, Y. pestis uses fleas to infect new hosts and has killed millions. A small set of genetic changes has contributed to the emergence of Y. pestis by allowing it to thrive inside a flea and maximise its transmission. In particular, some of these mutations have led to the bacteria being able to come together to form a sticky layer that adheres to the gut of the insect, with this 'biofilm' stopping the flea from feeding on blood. The starving flea keeps trying to feed, and with each bite comes another opportunity for Y. pestis to jump host. However, it remains unclear exactly how the mutations have influenced biofilm formation to allow for this new transmission mechanism to take place. To examine this phenomenon, Guo et al. focused on rcsD, a gene that codes for a component of the signalling system that controls biofilm creation. In Y. pestis this sequence has been mutated to become a 'pseudogene', a type of sequence which is often thought to be non-functional. However, the experiments showed that, in Y. pestis, rcsD could produce small amounts of a full-length RcsD protein similar to the one found in Y. pseudotuberculosis. However, the gene mostly produces a short 'RcsD-Hpt' protein that can, in turn, alter the expression of many genes, including those that decrease biofilm formation. This may prove to be beneficial for Y. pestis, for example when the bacteria switches from living in fleas to living in humans, where it does not require a biofilm. Guo et al. further investigated the impact of rcsD becoming a pseudogene inY. pestis, showing that if normal amounts of the full-length RcsD protein are produced, the bacteria quickly lose the gene that allows them to form biofilm in fleas, and cause disease in humans. In fact, additional analyses revealed that all sequenced strains of ancient and modern Y. pestis bacteria can produce RcsD-Hpt, even if they do not carry the same exact rcsD mutation. Overall, these results indicate that rcsD turning into a pseudogene marked an important step in the emergence of Y. pestis strains that can cause lasting plague outbreaks. They also point towards pseudogenes having more important roles in evolution than previously thought.

The Yersinia pestis Rcs phosphorelay inhibits biofilm formation by repressing transcription of the diguanylate cyclase gene hmsT.

Yersinia pestis, which causes bubonic plague, forms biofilms in fleas, its insect vectors, as a means to enhance transmission. Biofilm development is positively regulated by hmsT, encoding a diguanylate cyclase that synthesizes the bacterial second messenger cyclic-di-GMP. Biofilm development is negatively regulated by the Rcs phosphorelay signal transduction system. In this study, we show that Rcs-negative regulation is accomplished by repressing transcription of hmsT.

Application of combined CRISPR screening for genetic and chemical-genetic interaction profiling in Mycobacterium tuberculosis.

CRISPR screening, including CRISPR interference (CRISPRi) and CRISPR-knockout (CRISPR-KO) screening, has become a powerful technology in the genetic screening of eukaryotes. In contrast with eukaryotes, CRISPR-KO screening has not yet been applied to functional genomics studies in bacteria. Here, we constructed genome-scale CRISPR-KO and also CRISPRi libraries in Mycobacterium tuberculosis (Mtb). We first examined these libraries to identify genes essential for Mtb viability. Subsequent screening identified dozens of genes associated with resistance/susceptibility to the antitubercular drug bedaquiline (BDQ). Genetic and chemical validation of the screening results suggested that it provided a valuable resource to investigate mechanisms of action underlying the effects of BDQ and to identify chemical-genetic synergies that can be used to optimize tuberculosis therapy. In summary, our results demonstrate the potential for efficient genome-wide CRISPR-KO screening in bacteria and establish a combined CRISPR screening approach for high-throughput investigation of genetic and chemical-genetic interactions in Mtb.

A Series of Efficient Umbrella Modeling Strategies to Track Irradiation-Mutation Strains Improving Butyric Acid Production From the Pre-development Earlier Stage Point of View.

Clostridium tyrobutyricum (C. tyrobutyricum) is a fermentation strain used to produce butyric acid. A promising new biofuel, n-butanol, can be produced by catalysis of butyrate, which can be obtained through microbial fermentation. Butyric acid has various uses in food additives and flavor agents, antiseptic substances, drug formulations, and fragrances. Its use as a food flavoring has been approved by the European Union, and it has therefore been listed on the EU Lists of Flavorings. As butyric acid fermentation is a cost-efficient process, butyric acid is an attractive feedstock for various biofuels and food commercialization products. 12C6+ irradiation has advantages over conventional mutation methods for fermentation production due to its dosage conformity and excellent biological availability. Nevertheless, the effects of these heavy-ion irradiations on the specific productiveness of C. tyrobutyricum are still uncertain. We developed non-structured mathematical models to represent the heavy-ion irradiation of C. tyrobutyricum in biofermentation reactors. The kinetic models reflect various fermentation features of the mutants, including the mutant strain growth model, butyric acid formation model, and medium consumption model. The models were constructed based on the Markov chain Monte Carlo model and logistic regression. Models were verified using experimental data in response to different initial glucose concentrations (0-180 g/L). The parameters of fixed proposals are applied in the various fermentation stages. Predictions of these models were in accordance well with the results of fermentation assays. The maximum butyric acid production was 56.3 g/L. Our study provides reliable information for increasing butyric acid production and for evaluating the feasibility of using mutant strains of C. tyrobutyricum at the pre-development phase.

A CRISPR-Assisted Nonhomologous End-Joining Strategy for Efficient Genome Editing in Mycobacterium tuberculosis.

New tools for genetic manipulation of Mycobacterium tuberculosis are needed for the development of new drug regimens and vaccines aimed at curing tuberculosis infections. Clustered regularly interspaced short palindromic repeat (CRISPR)-CRISPR-associated protein (Cas) systems generate a highly specific double-strand break at the target site that can be repaired via nonhomologous end joining (NHEJ), resulting in the desired genome alteration. In this study, we first improved the NHEJ repair pathway and developed a CRISPR-Cas-mediated genome-editing method that allowed us to generate markerless deletion in Mycobacterium smegmatis, Mycobacterium marinum, and M. tuberculosis Then, we demonstrated that this system could efficiently achieve simultaneous generation of double mutations and large-scale genetic mutations in M. tuberculosis Finally, we showed that the strategy we developed can also be used to facilitate genome editing in Escherichia coliIMPORTANCE The global health impact of M. tuberculosis necessitates the development of new genetic tools for its manipulation, to facilitate the identification and characterization of novel drug targets and vaccine candidates. Clustered regularly interspaced short palindromic repeat (CRISPR)-CRISPR-associated protein (Cas) genome editing has proven to be a powerful genetic tool in various organisms; to date, however, attempts to use this approach in M. tuberculosis have failed. Here, we describe a genome-editing tool based on CRISPR cleavage and the nonhomologous end-joining (NHEJ) repair pathway that can efficiently generate deletion mutants in M. tuberculosis More importantly, this system can generate simultaneous double mutations and large-scale genetic mutations in this species. We anticipate that this CRISPR-NHEJ-assisted genome-editing system will be broadly useful for research on mycobacteria, vaccine development, and drug target profiling.

MicroRNA-143-5p targeting eEF2 gene mediates intervertebral disc degeneration through the AMPK signaling pathway.

BACKGROUND: Intervertebral disc degeneration (IDD) is a major contributor to back, neck, and radicular pain, and the treatment of IDD is costly and relatively ineffective. Dysregulation of microRNAs (miRNAs) has been reported to be involved in IDD. The purpose of our study is to illustrate the potential that miR-143-5p targeting eEF2 gene mediates IDD. METHODS: Following the establishment of the IDD rat models, expression of miR-143-5p, eEF2, Bcl-2, Bax, AMPK, mTOR, cyclinD, COL2, ACAN, and DCN was detected. The NP cells isolated from degenerative intervertebral disc (IVD) were introduced with a series of mimic, inhibitor, or AICAR to explore the functional role of miR-143-5p in IDD and to characterize the relationship between miR-143-5p and eEF2. Cell viability, cell cycle, apoptosis, and senescence were also evaluated. RESULTS: A reduction in eEF2, an increase in miR-143-5p, and activation of the AMPK signaling pathway were observed in degenerative IVD. Moreover, increased senescent NP cells were observed in degenerative IVD. eEF2 was confirmed as a target gene of miR-143-5p. miR-143-5p was found to activate the AMPK signaling pathway. The restoration of miR-143-5p or the activation of AMPK signaling pathway decreased COL2, ACAN, and DCN expression, coupled with the inhibition of NP cell proliferation and differentiation, and promotion of NP apoptosis and senescence. On the contrary, the inhibition of miR-143-5p led to the reversed results. CONCLUSION: The results demonstrated that the inhibition of miR-143-5p may act as a suppressor for the progression of IDD.

Correlation analysis between short-term insulin-like growth factor-I and glucose intolerance status after transsphenoidal adenomectomy in acromegalic patients: a large retrospective study from a single center in China.

OBJECTIVES: Our study aimed to investigate the associations of glucose tolerance status with insulin-like growth factor-I (IGF-I) and other clinical laboratory parameters of acromegalic patients before and after the patients underwent transsphenoidal adenomectomy (TSA) by conducting a single-center, retrospective study. SUBJECTS AND METHODS: A total of 218 patients with acromegaly who had undergone TSA as the first treatment were retrospectively analyzed. Serum IGF-I, growth hormone (GH) and glucose levels were measured before and after surgery. RESULTS: The follow-up levels for random GH, GH nadir, and the percentage of the upper limit of normal IGF-I (%ULN IGF-I) were decreased significantly. The percentages of normal (39.0%), early carbohydrate metabolism disorders (33.0%) and diabetes mellitus (28.0%) changed to 70.2%, 16.5% and 13.3%, respectively, after TSA. %ULN IGF-I at baseline was higher in the diabetes mellitus (DM) group than in the normal glucose tolerance group and impaired glucose tolerance (IGT) /impaired fasting glucose (IFG) groups before TSA, and the DM group exhibited a greater reduction in %ULN IGF-I value after surgery. The follow-up %ULN IGF-I value after surgery was significantly lower in the improved group, and Pearson's correlation analysis revealed that the reductions in %ULN IGF-I corresponded with the reductions in glucose level. CONCLUSION: This study examined the largest reported sample with complete preoperative and follow-up data. The results suggest that the age- and sex-adjusted IGF-I level, which reflects altered glucose metabolism, and the change of it are associated with improved glucose tolerance in acromegalic patients both before and after TSA.

AU-Rich Long 3' Untranslated Region Regulates Gene Expression in Bacteria.

3' untranslated regions (3' UTRs) and particularly long 3' UTRs have been shown to act as a new class of post-transcriptional regulatory element. We previously reported that hmsT mRNA stability is negatively regulated by the 3' UTR of hmsT in Yersinia pestis. To investigate more general effects of 3' UTRs in Y. pestis, we selected 15 genes potentially possessing long 3' UTRs with different AU content and constructed their 3' UTR deletion mutants. Deletion of AU-rich 3' UTRs increased mRNA levels, whereas deletion of 3' UTRs with normal AU content resulted in slight or no changes in the mRNA level. In addition, we found that PNPase was important for 3' UTR-mediated mRNA decay when the transcriptional terminator was Rho-dependent. Finally, we showed that ribosomes promote mRNA stability when bound to a 3' UTR. Our findings suggest that functional 3' UTRs might be broadly distributed in bacteria and their novel regulatory mechanisms require further investigation.

Sec16A, a key protein in COPII vesicle formation, regulates the stability and localization of the novel ubiquitin ligase RNF183.

We identified 37 ubiquitin ligases containing RING-finger and transmembrane domains. Of these, we found that RNF183 is abundantly expressed in the kidney. RNF183 predominantly localizes to the endoplasmic reticulum (ER), Golgi, and lysosome. We identified Sec16A, which is involved in coat protein complex II vesicle formation, as an RNF183-interacting protein. RNF183 colocalized with Sec16A and interacted through the central conserved domain (CCD) of Sec16A. Although Sec16A is not a substrate for RNF183, RNF183 was more rapidly degraded by the ER-associated degradation (ERAD) in the absence of Sec16A. Sec16A also stabilized the interacting ubiquitin ligase RNF152, which localizes to the lysosome and has structural similarity with RNF183. These results suggest that Sec16A appears to regulate the protein stability and localization of lysosomal ubiquitin ligases.

New Insights into the Non-orthodox Two Component Rcs Phosphorelay System.

The Rcs phosphorelay system, a non-orthodox two-component regulatory system, integrates environmental signals, regulates gene expression, and alters the physiological behavior of members of the Enterobacteriaceae family of Gram-negative bacteria. Recent studies of Rcs system focused on protein interactions, functions, and the evolution of Rcs system components and its auxiliary regulatory proteins. Herein we review the latest advances on the Rcs system proteins, and discuss the roles that the Rcs system plays in the environmental adaptation of various Enterobacteriaceae species.