Mass Spectrometry-Based Workflow for the Identification and Quantification of Alternative and Canonical Proteins in Pancreatic Cancer Cells.

The identification of small proteins and proteins produced from unannotated open reading frames (called alternative proteins or AltProts) has changed our vision of the proteome and has attracted more and more attention from the scientific community. Despite several studies investigating particular AltProts in diseases and demonstrating their importance in such context, we are still missing data on their expression and functions in many pathologies. Among these, pancreatic ductal adenocarcinoma (PDAC) is a particularly relevant case to study alternative proteins.

Non-random spatial organization of telomeres varies during the cell cycle and requires LAP2 and BAF.

Spatial genome organization within the nucleus influences major biological processes and is impacted by the configuration of linear chromosomes. Here, we applied 3D spatial statistics and modeling on high-resolution telomere and centromere 3D-structured illumination microscopy images in cancer cells. We found a multi-scale organization of telomeres that dynamically evolved from a mixed clustered-and-regular distribution in early G1 to a purely regular distribution as cells progressed through the cell cycle.

Known knowns, known unknowns and unknown unknowns in prokaryotic transposition.

Although the phenomenon of transposition has been known for over 60 years, its overarching importance in modifying and streamlining genomes took some time to recognize. In spite of a robust understanding of transposition of some TE, there remain a number of important TE groups with potential high genome impact and unknown transposition mechanisms and yet others, only recently identified by bioinformatics, yet to be formally confirmed as mobile. Here, we point to some areas of limited understanding concerning well established important TE groups with DDE Tpases, to address central gaps in our knowledge of characterised Tn with other types of Tpases and finally, to highlight new potentially mobile DNA species.

Everyman's Guide to Bacterial Insertion Sequences.

The number and diversity of known prokaryotic insertion sequences (IS) have increased enormously since their discovery in the late 1960s. At present the sequences of more than 4000 different IS have been deposited in the specialized ISfinder database. Over time it has become increasingly apparent that they are important actors in the evolution of their host genomes and are involved in sequestering, transmitting, mutating and activating genes, and in the rearrangement of both plasmids and chromosomes.

A TALE of transposition: Tn3-like transposons play a major role in the spread of pathogenicity determinants of Xanthomonas citri and other xanthomonads.

Unlabelled: Members of the genus Xanthomonas are among the most important phytopathogens. A key feature of Xanthomonas pathogenesis is the translocation of type III secretion system (T3SS) effector proteins (T3SEs) into the plant target cells via a T3SS. Several T3SEs and a murein lytic transglycosylase gene (mlt, required for citrus canker symptoms) are found associated with three transposition-related genes in Xanthomonas citri plasmid pXAC64.

Bacterial insertion sequences: their genomic impact and diversity.

Insertion sequences (ISs), arguably the smallest and most numerous autonomous transposable elements (TEs), are important players in shaping their host genomes. This review focuses on prokaryotic ISs. We discuss IS distribution and impact on genome evolution.

The diversity of prokaryotic DDE transposases of the mutator superfamily, insertion specificity, and association with conjugation machineries.

Transposable elements (TEs) are major components of both prokaryotic and eukaryotic genomes and play a significant role in their evolution. In this study, we have identified new prokaryotic DDE transposase families related to the eukaryotic Mutator-like transposases. These genes were retrieved by cascade PSI-Blast using as initial query the transposase of the streptococcal integrative and conjugative element (ICE) TnGBS2.

ISsaga is an ensemble of web-based methods for high throughput identification and semi-automatic annotation of insertion sequences in prokaryotic genomes.

Insertion sequences (ISs) play a key role in prokaryotic genome evolution but are seldom well annotated. We describe a web application pipeline, ISsaga (http://issaga.biotoul.

The arthrobacter arilaitensis Re117 genome sequence reveals its genetic adaptation to the surface of cheese.

Arthrobacter arilaitensis is one of the major bacterial species found at the surface of cheeses, especially in smear-ripened cheeses, where it contributes to the typical colour, flavour and texture properties of the final product. The A. arilaitensis Re117 genome is composed of a 3,859,257 bp chromosome and two plasmids of 50,407 and 8,528 bp.

Route 66: investigations into the organisation and distribution of the IS66 family of prokaryotic insertion sequences.

We have analysed a large number of members of the IS66 family of prokaryotic insertion sequences which include three orfs (A, B and C) and we show that these are closely related to a second group (ISBst12) which includes only orfC, encoding the transposase TnpC. These two IS groups are also related by their terminal inverted repeats (IR) which show significant conservation. We propose that both groups be included in the same family, the IS66 family.