Late‐onset retinal degeneration pathology due to mutations in CTRP5 is mediated through HTRA1

Late‐onset retinal degeneration (L‐ORD) is an autosomal dominant macular degeneration characterized by the formation of sub‐retinal pigment epithelium (RPE) deposits and neuroretinal atrophy. L‐ORD results from mutations in the C1q‐tumor necrosis factor‐5 protein (CTRP5), encoded by the CTRP5/C1QTNF5 gene. To understand the mechanism underlying L‐ORD pathology, we used a human cDNA library yeast two‐hybrid screen to identify interacting partners of CTRP5. Additionally, we analyzed the Bruch's membrane/choroid (BM‐Ch) from wild‐type (Wt), heterozygous S163R Ctrp5 mutation knock‐in (Ctrp5^S163R/wt), and homozygous knock‐in (Ctrp5^S163R/S163R) mice using mass spectrometry. Both approaches showed an association between CTRP5 and HTRA1 via its C‐terminal PDZ‐binding motif, stimulation of the HTRA1 protease activity by CTRP5, and CTRP5 serving as an HTRA1 substrate. The S163R‐CTRP5 protein also binds to HTRA1 but is resistant to HTRA1‐mediated cleavage. Immunohistochemistry and proteomic analysis showed significant accumulation of CTRP5 and HTRA1 in BM‐Ch of Ctrp5^S163R/S163R and Ctrp5^S163R/wt mice compared with Wt. Additional extracellular matrix (ECM) components that are HTRA1 substrates also accumulated in these mice. These results implicate HTRA1 and its interaction with CTRP5 in L‐ORD pathology.     

Community structure,spatial distribution,diversity and functional characterization of culturable endophytic fungi associated with Glycyrrhiza glabra L.

A total of 266 endophytic fungal isolates were recovered from 1019 tissue segments of Glycyrrhiza glabra collected from four different locations in the North-Western Himalayas. The endophytes grouped into 21 genera and 38 different taxa. The host had strong affinity for the genus Phoma, followed by Fusarium. The species richness was highest at the sub-tropical location, followed by the sub-temperate location and the temperate locations, respectively. The tissue specificity of endophytes was also evident. Some endophytes showed potential antimicrobial activity against phyto-pathogens indicating that they may be helpful to the host in evading pathogens. All the endophytic taxa produced the plant growth promoting hormone, indole acetic acid (IAA), though in varying concentrations. None of these endophytes caused any symptoms of disease in co-cultivation with the tissue cultured plants. Further, all the endophytes had a positive influence on the phenolic and flavonoid content of the host. Three endophytes, Stagonosporopsis cucurbitacearum, Bionectria sp. and Aspergillus terreus also increased the host root (rhizome) and shoot growth visibly. Such endophytes are potential candidates for developing endophyte-based technologies for sustainable cultivation and enhanced productivity of G. glabra. This is the first report of community structure and biological properties of fungal endophytes associated with G. glabra.     

Metabolic coupling in the co-cultured fungal-yeast suite of Trametes ljubarskyi and Rhodotorula mucilaginosa leads to hypersecretion of laccase isozymes

Trametes ljubarskyi produces multiple laccase isozymes under various physicochemical conditions. During co-cultivation condition Rhodotorula mucilaginosa showed inter-specific interactions with T. ljubarskyi and hypersecretion of laccases; however, the underlying molecular mechanism is less-known. The analysis of proteomics data of co-cultivated cultures revealed the mechanism of metabolic coupling during fungal-yeast interactions. The results suggested high score GO terms related to stimulus-response, protein binding, membrane components, transport channels, oxidoreductases, and antioxidants. The SEM studies confirmed the cellular communication and their inter-specific interactions. This study allows us to deepen and refine our understanding of fungal-yeast symbiotic interaction; further, it also establishes a mutual relation by metabolic coupling for 10-fold higher laccase isozyme secretion (6532 U/ml). The purified laccase isozymes showed acidic pH optima (pH 3–4), higher thermo-stability (60 °C), and broad enzyme kinetics (K_m) values. Our study also provides an in-depth understanding of laccase isozymes and their potential to degrade synthetic dyes, which may help the fungi to survive in an adverse environment.     

Correlating single cell motility with population growth dynamics for flagellated bacteria

Many bacteria used for biotechnological applications are naturally motile. Their "bio-nanopropeller" driven movement allows searching for better environments in a process called chemotaxis. Since bacteria are extremely small in size compared to the bulk fluid volumes in bioreactors, single cell motility is not considered to influence bioreactor operations. However, with increasing interest in localized fluid flow inside reactors, it is important to ask whether individual motility characteristics of bacteria are important in bioreactor operations. The first step in this direction is to try to correlate single cell measurements with population data of motile bacteria in a bioreactor. Thus, we observed the motility behavior of individual bacterial cells, using video microscopy with 33 ms time resolution, as a function of population growth dynamics of batch cultures in shake flasks. While observing the motility behavior of the most intensively studied bacteria, Escherichia coli, we find that overall bacterial motility decreases with progression of the growth curve. Remarkably, this is due to a decrease in a specific motility behavior called "running". Our results not only have direct implications on biofilm formations, but also provide a new direction in bioprocess design research highlighting the role of individual bacterial cell motility as an important parameter.     

In vitro and in silico molecular interaction of multiphase nanoparticles containing inositol hexaphosphate and jacalin: Therapeutic potential against colon cancer cells (HCT-15)

Inositol hexaphosphate (IP6) is a natural constituent found in almost all cereals and legumes. It is known to cause numerous antiangiogenic manifestations. Notwithstanding its great potential, it is underutilized due to the chelation and rapid excretion from the body. Jacalin is another natural constituent obtained from seeds of jackfruit and can target disaccharides overexpressed in tumor cells. The current study was in-quested to develop and evaluate a surface-modified gold nanoparticulate system containing IP6 and jacalin which may maximize the apoptotic effect of IP6 against HCT-15 cell lines. IP6 loaded jacalin-pectin-gold nanoparticles (IJP-GNPs) were developed through reduction followed by incubation method. The developed formulation was tested for various in vitro and in silico studies to investigate its potential. HCT-15 cells when exposed to IJP-GNP resulted in significant apoptotic effects in dose as well as time-dependent manner, as measured using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, micronucleus, and reactive oxygen species assay. IJP-GNP displayed cell cycle arrest at the G0/G1 phase. To further explore the mechanism of chemoprevention, in silico studies were performed. The docking results revealed that the interactive behavior of IP6, P-GNP, and jacalin could target and inhibit the tumor formation activity, supported by in vitro studies. Taken together, all the findings suggested that IP6 loaded nanoparticles may increase the hope of future drug delivery strategy for targeting colon cancer.     

Leptin secreted from testicular microenvironment modulates hedgehog signaling to augment the endogenous function of Leydig cells

Although testosterone deficiency (TD) may be present in one out of five men 40 years or older, the factors responsible for TD remain largely unknown. Leydig stem cells (LSCs) differentiate into adult Leydig cells (ALC) and produce testosterone in the testes under the pulsatile control of luteinizing hormone (LH) from the pituitary gland. However, recent studies have suggested that the testicular microenvironment (TME), which is comprised of Sertoli and peritubular myoid cells (PMC), plays an instrumental role in LSC differentiation and testosterone production under the regulation of the desert hedgehog signaling pathway (DHH). It was hypothesized that the TME releases paracrine factors to modulate LSC differentiation. For this purpose, cells (Sertoli, PMCs, LSCs, and ALCs) were extracted from men undergoing testis biopsies for sperm retrieval and were evaluated for the paracrine factors in the presence or absence of the TME (Sertoli and PMC). The results demonstrated that TME secretes leptin, which induces LSC differentiation and increases testosterone production. Leptin’s effects on LSC differentiation and testosterone production, however, are inversely concentration-dependent: positive at low doses and negative at higher doses. Mechanistically, leptin binds to the leptin receptor on LSCs and induces DHH signaling to modulate LSC differentiation. Leptin-DHH regulation functions unidirectionally insofar as DHH gain or loss of function has no effect on leptin levels. Taken together, these findings identify leptin as a key paracrine factor released by cells within the TME that modulates LSC differentiation and testosterone release from mature Leydig cells, a finding with important clinical implications for TD.Subject terms: Stem-cell differentiation, Translational research     

Mycobacterium tuberculosis carbon and nitrogen metabolic fluxes

Mycobacterium tuberculosis (Mtb) is one of the most formidable pathogens causing tuberculosis (TB), a devastating infectious disease responsible for the highest human mortality and morbidity. The emergence of drug-resistant strains of the pathogen has increased the burden of TB tremendously and new therapeutics to overcome the problem of drug resistance are urgently needed. Metabolism of Mtb and its interactions with the host is important for its survival and virulence; this is an important topic of research where there is growing interest in developing new therapies and drugs that target these interactions and metabolism of the pathogen during infection. Mtb adapts its metabolism in its intracellular niche and acquires multiple nutrient sources from the host cell. Carbon metabolic pathways and fluxes of Mtb has been extensively researched for over a decade and is well-defined. Recently, there has been investigations and efforts to measure metabolism of nitrogen, which is another important nutrient for Mtb during infection. This review discusses our current understanding of the central carbon and nitrogen metabolism, and metabolic fluxes that are important for the survival of the TB pathogen.     

Identification of a site on mannan-binding lectin critical for enhancement of phagocytosis

Mannan-binding lectin (MBL) constitutes an important part of the human innate immune defense system. It has been shown to mediate the activation of complement upon binding to specific microbial carbohydrate motifs, to directly opsonize organisms, and to enhance the phagocytosis of targets suboptimally opsonized with IgG or complement components C3b or C4b. This enhancement of phagocytic activity induced by MBL and other molecules that contain a collagen-like region contiguous with a pattern recognition domain is mediated by a 126,000 M(r) surface glycoprotein, designated C1qR(P). Although it has been known that the collagen-like domain of these "defense collagens" contains the interaction site(s) that triggers this enhancement of uptake, the specific interaction site has not been identified. To address this issue, wild type and mutant MBL constructs were generated, inserted into baculovirus, expressed in Sf9 cells, and the recombinant MBL (rMBL) proteins purified by mannan affinity chromatography. The effect of wild type and mutant rMBL on the phagocytosis of targets suboptimally opsonized with IgG or with IgM and C4b by human peripheral blood monocytes was then assessed. Two mutants, one of which has five GXY triplets deleted below the kink region of MBL and the other one having only two of the GXY triplets deleted below the kink, failed to enhance phagocytosis, suggesting the importance of the specific sequence GEKGEP in stimulating phagocytic activity. Similar sequences were detected in other defense collagens, implicating the consensus motif GE(K/Q/R)GEP as critical in mediating the enhancement of phagocytosis through C1qR(P.) Clarification of specific ligand-C1qR(P) interactions should facilitate the investigation of the signal transduction processes involved in the cell activation, as well as provide the basis for the design of specific modulators of the functions mediated by this receptor.     

Fine needle aspiration cytology of sclerosing lobular hyperplasia of the breast: a case report

BACKGROUND: Sclerosing lobular hyperplasia presenting as a palpable, circumscribed nodular mass in a young female's breast is characterized histologically by prominent hyperplasia of the lobules and sclerosis of the intralobular connective tissue. The cytomorphologic features and differential diagnosis of the lesion are presented. CASE: A 14-year-old female presented with a painless, progressively increasing, nodular, firm, mobile lump measuring 5 x 5 cm in the right breast. The clinical and radiologic diagnosis was fibroadenoma. Fine needle aspiration smears showed a clean background with uniform, round to oval epithelial cells in flat sheets, round clusters and rosettelike (acinar) arrangements. A few naked nuclei were present, while stromal fragments were not seen. CONCLUSION: When analyzed in the context of the clinical findings, the cytologic features of sclerosing lobular hyperplasia help to differentiate it from other benign palpable nodular lesions of the juvenile breast.