Search bioRxivSearch

Biology subjects

Rokka, A.

Publications and source records attributed to Rokka, A..

2 recordsLinked to original sources

Data-independent acquisition mass spectrometry enables reproducible characterization of microbiota function

Metaproteomics is an emerging research area which aims to reveal the functionality of microbial communities - unlike the increasingly popular metagenomics providing insights only on the functional potential. So far, the common approach in metaproteomics has been data-dependent acquisition mass spectrometry (DDA). However, DDA is known to have limited reproducibility and dynamic range with samples of complex microbial composition. To overcome these limitations, we introduce here a novel approach utilizing data-independent acquisition (DIA) mass spectrometry, which has not been applied in metaproteomics of complex samples before. For robust analysis of the data, we introduce an open-source software package diatools, which is freely available at Docker Hub and runs on various operating systems. Our highly reproducible results on laboratory-assembled microbial mixtures and human fecal samples support the utility of our approach for functional characterization of complex microbiota. Hence, the approach is expected to dramatically improve our understanding on the role of microbiota in health and disease.

microbiology

GGA2 and RAB13 regulate activity-dependent β1-integrin recycling

{beta}1-integrins mediate cell-matrix interactions and their trafficking is important in the dynamic regulation of cell adhesion, migration and malignant processes like cancer cell invasion. Here we employ an RNAi screen to characterize regulators of integrin traffic and identify the association of Golgi-localized gamma ear-containing Arf-binding protein 2 (GGA2) with {beta}1-integrin and its role in recycling of the active but not inactive {beta}1-integrin receptors. Silencing of GGA2 limits active {beta}1-integrin levels in focal adhesions and decreases cancer cell migration and invasion congruent with its ability to regulate the dynamics of active integrins. Using the proximity-dependent biotin identification (BioID) method, we identify two RAB family small GTPases, RAB13 and RAB10, associating with GGA2 and {beta}1-integrin. Functionally, RAB13 silencing triggers the intracellular accumulation of active {beta}1-integrin, reduces integrin activity, in focal adhesions, and cell migration, similarly to GGA2 depletion, indicating that both facilitate active {beta}1-integrin recycling the plasma membrane. Thus, GGA2 and RAB13 are important specificity determinants for integrin activity-dependent traffic.

cell biology