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Hauth, J.

Publications and source records attributed to Hauth, J..

2 recordsLinked to original sources

Differential degradation of RNA species by autophagy related pathways in plants

An important function of the plant vacuole is the recycling of the delivered proteins and RNA by autophagy. We provide the first plant vacuolar small RNome by isolation of intact vacuoles from Barley and Arabidopsis, subsequent RNA purification and Next Generation Sequencing. In these vacuolar sRNomes, all types of cellular RNAs were found including those of chloroplast origin, suggesting a bulk-type of RNA transfer to, and breakdown in vacuoles. ATG5 is a major representative of autophagy genes and the vacuolar RNA composition in corresponding knockout plants differed clearly from controls as most chloroplast derived RNA species were missing. Moreover, the read length distribution of RNAs found in ATG5 mutants differed to control samples, indicating altered RNA processing. In contrast, vacuolar RNA length and composition of plants lacking the vacuolar RNase2 (rns2-2), involved in cellular RNA homeostasis, showed minor alterations, only. Our data therefore suggests that mainly autophagy components are responsible for selective transport and targeting of different RNA species into the vacuole for degradation. In addition, mature miRNAs were detected in all vacuolar preparations, however in ATG5 mutants at much lower frequency, indicating a new biological role for vacuolar miRNAs apart from becoming degraded.

plant biology↗

Improved FRAP measurements on biofilms

We expand the standard FRAP model introduced by Axelrod et al. in 1976. Our goal is to capture some common artifacts observed in the fluorescence measurements obtained with a confocal laser scanning microscope (CLSM) in biofilms: 1) linear drift, 2) exponential decrease (due to bleaching during the measurements), 3) stochastic Gaussian noise, and 4) uncertainty in the exact time point of the onset of fluorescence recovery. In order to fit the resulting stochastic model to data from FRAP measurements and to estimate all unknown model parameters, we apply a suitably adapted Metropolis-Hastings algorithm. In this way, a more accurate estimation of the diffusion coefficient of the fluorophore is achieved. The method was tested on data obtained from FRAP measurements on a cultivated biofilm.\n\nSTATEMENT OF SIGNIFICANCEDiffusion and mass transport in biofilms is presumed to play an important role in the resistance against antimicrobial agents and the secretion thereof. FRAP measurements give insight into these transport processes. In this article, the authors expand the standard FRAP model by a blackbox part which addresses some artifacts commonly observed in the measurements. This is done in order to improve the estimations of diffusion coefficients considerably, aiming at a more comprehensive description of diffusion processes inside the biofilm. We expect that the methods are transferable to FRAP measurements on materials other than biofilms.

bioinformatics↗