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Butt, L.

Publications and source records attributed to Butt, L..

2 recordsLinked to original sources

An optimized electroporation approach for efficient CRISPR/Cas9 genome editing in murine zygotes

Electroporation of zygotes represents a rapid alternative to the elaborate pronuclear injection procedure for CRISPR/Cas9-mediated genome editing in mice. However, current protocols for electroporation either require the investment in specialized electroporators or corrosive pre-treatment of zygotes which compromises embryo viability. Here, we describe an easily adaptable approach for the introduction of specific mutations in C57BL/6N mice by electroporation of intact zygotes using a common electroporator with synthetic CRISPR/Cas9 components and minimal technical requirement. Direct comparison to conventional pronuclear injection demonstrates significantly reduced physical damage and thus improved embryo development with successful genome editing in up to 100% of living offspring. Hence, our novel approach for Easy Electroporation of Zygotes (EEZy) allows highly efficient generation of CRISPR/Cas9 transgenic mice while reducing the numbers of animals required.

genetics

Individual nephron proteomes connect morphology and function in proteinuric kidney disease

In diseases of many parenchymatous organs, heterogenous detoriation of individual functional units determines the clinical prognosis. However, the molecular characterization of these subunits remains a technological challenge that needs to be addressed in order to better understand pathological mechanisms. Sclerotic and proteinuric glomerular kidney disease is a frequent and heterogeneous disease which affects a fraction of nephrons, glomeruli and draining tubules, to variable extents, and for which no treatment exists. Here, we developed and applied an antibody-independent methodology to investigate heterogeneity of individual nephron segment proteomes from mice with proteinuric kidney disease. This \"one-segment-one-proteome-approach\" defines mechanistic connections between upstream (glomerular) and downstream (tubular) nephron segment populations. In single glomeruli from two different mouse models of sclerotic glomerular disease, we identified a coherent protein expression module consisting of extracellular matrix protein deposition (reflecting glomerular sclerosis), glomerular albumin (reflecting proteinuria) and LAMP1, a lysosomal protein. This module was associated with a loss of podocyte marker proteins. In an attempt to target this protein co-expression module, genetic ablation of LAMP1-correlated lysosomal proteases in mice could ameliorate glomerular damage. Furthermore, individual glomeruli from patients with genetic sclerotic and non-sclerotic proteinuric diseases demonstrated increased abundance of lysosomal proteins, in combination with a decreased abundance of the mutated gene products. Therefore, increased glomerular lysosomal load is a conserved key mechanism in proteinuric kidney diseases, and the technology applied here can be implemented to address heterogeneous pathophysiology in a variety of diseases at a sub-biopsy scale

physiology