Characterizing the normal proteome of human ciliary body

Background

The ciliary body is the circumferential muscular tissue located just behind the iris in the anterior chamber of the eye. It plays a pivotal role in the production of aqueous humor, maintenance of the lens zonules and accommodation by changing the shape of the crystalline lens. The ciliary body is the major target of drugs against glaucoma as its inhibition leads to a drop in intraocular pressure. A molecular study of the ciliary body could provide a better understanding about the pathophysiological processes that occur in glaucoma. Thus far, no large-scale proteomic investigation has been reported for the human ciliary body.

Results

In this study, we have carried out an in-depth LC-MS/MS-based proteomic analysis of normal human ciliary body and have identified 2,815 proteins. We identified a number of proteins that were previously not described in the ciliary body including importin 5 (IPO5), atlastin-2 (ATL2), B-cell receptor associated protein 29 (BCAP29), basigin (BSG), calpain-1 (CAPN1), copine 6 (CPNE6), fibulin 1 (FBLN1) and galectin 1 (LGALS1). We compared the plasma proteome with the ciliary body proteome and found that the large majority of proteins in the ciliary body were also detectable in the plasma while 896 proteins were unique to the ciliary body. We also classified proteins using pathway enrichment analysis and found most of proteins associated with ubiquitin pathway, EIF2 signaling, glycolysis and gluconeogenesis.

Conclusions

More than 95% of the identified proteins have not been previously described in the ciliary body proteome. This is the largest catalogue of proteins reported thus far in the ciliary body that should provide new insights into our understanding of the factors involved in maintaining the secretion of aqueous humor. The identification of these proteins will aid in understanding various eye diseases of the anterior segment such as glaucoma and presbyopia.     

Improved Electrochemical Analysis of Neuropathy Target Esterase Activity by a Tyrosinase Carbon Paste Electrode Modified by 1-Methoxyphenazine Methosulfate

A graphite-paste tyrosinase biosensor was improved by adding 1-methoxyphenazine methosulfate as a mediator. Mediator modification enhanced sensitivity to phenol 4-fold and long-term stability 3-fold. Phenol could be detected at 25 nM (S/N=2) using an Ag/AgCl reference electrode. The biosensor was used to measure the activity of a toxicologically significant enzyme, neuropathy target esterase (NTE), which yields phenol by hydrolysis of the substrate, phenyl valerate. Using the new biosensor, blood and brain NTE inhibition by organophosphorus (OP) compounds with different neuropathic potencies were well correlated (r=0.990, n=7), supporting the use of blood NTE as a biochemical marker of exposure to neuropathic OP compounds.     

FE65 as a link between VLDLR and APP to regulate their trafficking and processing

Background

Loss-of-function mutations in PTEN-induced kinase 1 (PINK1) have been linked to familial Parkinson??s disease, but the underlying pathogenic mechanism remains unclear. We previously reported that loss of PINK1 impairs mitochondrial respiratory activity in mouse brains.

Results

In this study, we investigate how loss of PINK1 impairs mitochondrial respiration using cultured primary fibroblasts and neurons. We found that intact mitochondria in PINK1?/? cells recapitulate the respiratory defect in isolated mitochondria from PINK1?/? mouse brains, suggesting that these PINK1?/? cells are a valid experimental system to study the underlying mechanisms. Enzymatic activities of the electron transport system complexes are normal in PINK1?/? cells, but mitochondrial transmembrane potential is reduced. Interestingly, the opening of the mitochondrial permeability transition pore (mPTP) is increased in PINK1?/? cells, and this genotypic difference between PINK1?/? and control cells is eliminated by agonists or inhibitors of the mPTP. Furthermore, inhibition of mPTP opening rescues the defects in transmembrane potential and respiration in PINK1?/? cells. Consistent with our earlier findings in mouse brains, mitochondrial morphology is similar between PINK1?/? and wild-type cells, indicating that the observed mitochondrial functional defects are not due to morphological changes. Following FCCP treatment, calcium increases in the cytosol are higher in PINK1?/? compared to wild-type cells, suggesting that intra-mitochondrial calcium concentration is higher in the absence of PINK1.

Conclusions

Our findings show that loss of PINK1 causes selective increases in mPTP opening and mitochondrial calcium, and that the excessive mPTP opening may underlie the mitochondrial functional defects observed in PINK1?/? cells.     

The abundance of an invasive freshwater snail Tarebia granifera (Lamarck, 1822) in the Nseleni River,South Africa

The invasive freshwater snail Tarebia granifera (Lamarck, 1822) was first reported in South Africa in 1999 and it has become widespread across the country, with some evidence to suggest that it reduces benthic macroinvertebrate biodiversity. The current study aimed to identify the primary abiotic drivers behind abundance patterns of T. granifera, by comparing the current abundance of the snail in three different regions, and at three depths, of the highly modified Nseleni River in KwaZulu-Natal, South Africa. Tarebia granifera was well established throughout the Nseleni River system, with an overall preference for shallow waters and seasonal temporal patterns of abundance. Although it is uncertain what the ecological impacts of the snail in this system are, its high abundances suggest that it should be controlled where possible and prevented from invading other systems in the region.     

Eulophidae (hymenoptera) parasitoids of Phyllonorycter apparella and phyllonorycter populifoliella (Lepidoptera, Gracillariidae), pests of Populus tremula and populus nigra in Ul’yanovsk province, Russia

Parasitoid complexes of two species of the genus Phyllonorycter (Ph. apparella and Ph. populifoliella) reared from 2 plants (Populus tremula and P. nigra) were studied in Ul’yanovsk Province, Russia. Twenty species of parasitoids are new for Ph. apparella and 12 are new for Ph. populifoliella. Minotetrastichus frontalis and Pnigalio agraules are the dominant species for both parasitoid complexes. The highest relative abundance was observed for Ph. apparella on Populus tremula (75%) and for Ph. populifoliella on P. nigra (61%). The parasitoid complexes of Ph. apparella and Ph. populifoliella show high similarity (the Jaccard coefficient is 0.65).     

The parasitic wasp <Emphasis Type="Italic">Baryscapus crassicornis</Emphasis> (Erdös) (Hymenoptera,Eulophidae) developing in larvae of the weevil genus <Emphasis Type="Italic">Larinus</Emphasis> germar (Coleoptera,Curculionidae)

Baryscapus crassicornis (Erdös) was reared from the last instar larvae of three species of Curculionidae: Larinus idoneus Gyllenhal, developing in the inflorescences of Jurinea cyanoides (L.), L. turbinatus (Gyllenhal), developing in Cirsium arvense (L.) in Russia (Ul’yanovsk Province), and L. latus (Herbst), developing in Onopordum acanthium L. and O. leptolepis DC. (Asteraceae) in Iran. Data on the parasitoid and its hosts biology, variation of morphological characters, and diagnostic notes are provided. The 3rd instar larva and the pupa of B. crassicornis are described for the first time.