Biomedical subjects

Benno Schindelholz

Publications and source records attributed to Benno Schindelholz.

3 recordsLinked to original sources

PubMed2003

Rheb is an essential regulator of S6K in controlling cell growth in Drosophila.

Understanding the mechanisms through which multicellular organisms regulate cell, organ and body growth is of relevance to developmental biology and to research on growth-related diseases such as cancer. Here we describe a new effector in growth control, the small GTPase Rheb (Ras homologue enriched in brain). Mutations in the Drosophila melanogaster Rheb gene were isolated as growth-inhibitors, whereas overexpression of Rheb promoted cell growth. Our genetic and biochemical analyses suggest that Rheb functions downstream of the tumour suppressors Tsc1 (tuberous sclerosis 1)-Tsc2 in the TOR (target of rapamycin) signalling pathway to control growth, and that a major effector of Rheb function is ribosomal S6 kinase (S6K).

Animals↗

PubMed2002

High-resolution SNP mapping by denaturing HPLC.

With the availability of complete genome sequences, new rapid and reliable strategies for positional cloning become possible. Single-nucleotide polymorphisms (SNPs) permit the mapping of mutations at a resolution not amenable to classical genetics. Here we describe a SNP mapping procedure that relies on resolving polymorphisms by denaturing HPLC without the necessity of determining the nature of the SNPs. With the example of mapping mutations to the Drosophila nicastrin locus, we discuss the benefits of this method, evaluate the frequency of closely linked and potentially misleading second site mutations, and demonstrate the use of denaturing high-performance liquid chromatography to identify mutations in the candidate genes and to fine-map chromosomal breakpoints. Furthermore, we show that recombination events are not uniformly dispersed over the investigated region but rather occur at hot spots.

Animals↗

PubMed2002

Combinatorial RNAi: a method for evaluating the functions of gene families in Drosophila.

Individual members of gene families often have partially redundant functions during nervous system development, making conventional genetic analysis problematic. Here we review experiments showing that several genes can be silenced together by injection of double-stranded RNAs into wild-type Drosophila embryos. By dye-labeling single neuroblasts in injected embryos, the effects of multigene silencing on individual CNS axon pathways can now be examined.

Animals↗