Proteomic alterations in early stage cervical cancer

Laser capture microdissection (LCM) allows the capture of cell types or welldefined structures in tissue. We compared in a semi-quantitative way the proteomes from an equivalent of 8,000 tumor cells from patients with squamous cell cervical cancer (SCC, n = 22) with healthy epithelial and stromal cells obtained from normal cervical tissue (n = 13). Proteins were enzymatically digested into peptides which were measured by high-resolution mass spectrometry and analyzed by "all-ornothing" analysis, Bonferroni, and Benjamini-Hochberg correction for multiple testing. By comparing LCM cell type preparations, 31 proteins were exclusively found in early stage cervical cancer (n = 11) when compared with healthy epithelium and stroma, based on criteria that address specificity in a restrictive "all-or-nothing" way. By Bonferroni correction for multiple testing, 30 proteins were significantly up-regulated between early stage cervical cancer and healthy control, including six members of the MCM protein family. MCM proteins are involved in DNA repair and expected to be participating in the early stage of cancer. After a less stringent Benjamini-Hochberg correction for multiple testing, we found that the abundances of 319 proteins were significantly different between early stage cervical cancer and healthy controls. Four proteins were confirmed in digests of whole tissue lysates by Parallel Reaction

Identification and molecular modelling of a mutation in the motor head domain of myosin VIIA in a family with autosomal dominant hearing impairment (DFNA11).

Contains fulltext : 58224.pdf (publisher's version ) (Closed access)Myosin VIIA is an unconventional myosin that has been implicated in Usher syndrome type 1B, atypical Usher syndrome, non-syndromic autosomal recessive hearing impairment (DFNB2) and autosomal dominant hearing impairment (DFNA11). Here, we present a family with non-syndromic autosomal dominant hearing impairment that clinically resembles the previously published DFNA11 family. The affected family members show a flat audiogram at young ages and only modest progression, most clearly at the high frequencies. In addition, they suffer from minor vestibular symptoms. Linkage analysis yielded a maximum two-point lodscore of 3.43 for marker D11S937 located within 1 cM of the myosin VIIA gene. The myosin VIIA gene was sequenced and 11 nucleotide variations were found. Ten nucleotide changes represent benign intronic variants, silent exon mutations or non-pathologic amino acid substitutions. One variant, a c.1373A-->T transversion that is heterozygously present in all affected family members and absent in 300 healthy individuals, is predicted to result in an Asn458Ile amino acid substitution. Asn458 is located in a region of the myosin VIIA motor domain that is highly conserved in different classes of myosins and in myosins of different species. To evaluate whether the Asn458Ile mutation was indeed responsible for the hearing impairment, a molecular model of myosin VIIA was built based on the known structure of the myosin II heavy chain from Dictyostelium discoideum. In this model, conformational changes in the protein caused by the amino acid substitution Asn458Ile are predicted to disrupt ATP/ADP binding and impair the myosin power-stroke, which would have a severe effect on the function of the myosin VIIA protein

Chondrule fragments from Comet Wild2: evidence for high temperature processing in the outer Solar System

AbstractTerminal grains from C2063,1,154,1,0 (Track 154) and C2061,1,113,5 (Track 113) from the Stardust collection of Comet Wild2's coma have been studied by TEM and NanoSIMS. Terminal grain 2 of C2063,1,154,1,0 consists of an Al-rich diopside (En 97–99%, Al2O3 9–11wt%), pigeonite (En 85% Wo 15% with TiO2 and Al2O3 contents of 0.5 and 5.2wt%) and minor forsterite and enstatite. The mineral assemblage and Al-rich, Ti-poor composition of the grain are consistent with being a fragment of an Al-rich chondrule, similar to those present in carbonaceous chondrites. The oxygen isotopic composition of the C2063,1,154,1,0 grain was determined by NanoSIMS analyses and found to be δ17O −10.6±5.7‰, δ18O −7.5±2.5‰ and δ17O +1.4±4.3‰, δ18O −6.5±1.6‰ (1σ errors) for the two sections. These figures are distinct from CAIs and consistent with an origin as Al-rich chondrule fragments. Terminal grain 5 of C2061,1,113,5 consists of low Ca pyroxene En 86–87% Fs 10–11% Wo 3–4% and ≤2wt% Al2O3 and in one section 5–10% of a Na-rich silicate phase. This assemblage may be a fragment of a low-Ca pyroxene-bearing chondrule and mesostasis. The original chondrule diameter for the C2063,1,154,1,0 and C2061,1,113,5 samples, by analogy with carbonaceous chondrite chondrules, might have been in the range 0.2–1.0mm. If they were of that size, then the presence of large grains of high temperature material (e.g. ≥1500K for such refractory assemblages) could be explained through commonly invoked models of radial drift from inner to outer Solar System, but only if the chondrules were first fragmented to dust within the inner Solar System. An alternative scenario is that some chondrule formation was associated with high temperature processing and planetesimals in the outer Solar System