Xpf suppresses the mutagenic consequences of phagocytosis in Dictyostelium.

As time passes, mutations accumulate in the genomes of all living organisms. These changes promote genetic diversity, but also precipitate ageing and the initiation of cancer. Food is a common source of mutagens, but little is known about how nutritional factors cause lasting genetic changes in the consuming organism.

The Fanconi anaemia components UBE2T and FANCM are functionally linked to nucleotide excision repair.

The many proteins that function in the Fanconi anaemia (FA) monoubiquitylation pathway initiate replicative DNA crosslink repair. However, it is not clear whether individual FA genes participate in DNA repair pathways other than homologous recombination and translesion bypass. Here we show that avian DT40 cell knockouts of two integral FA genes--UBE2T and FANCM are unexpectedly sensitive to UV-induced DNA damage.

Xpf and not the Fanconi anaemia proteins or Rev3 accounts for the extreme resistance to cisplatin in Dictyostelium discoideum.

Organisms like Dictyostelium discoideum, often referred to as DNA damage "extremophiles", can survive exposure to extremely high doses of radiation and DNA crosslinking agents. These agents form highly toxic DNA crosslinks that cause extensive DNA damage. However, little is known about how Dictyostelium and the other "extremophiles" can tolerate and repair such large numbers of DNA crosslinks.

A Dictyostelium homologue of the metazoan Cbl proteins regulates STAT signalling.

Cbl proteins downregulate metazoan signalling pathways by ubiquitylating receptor tyrosine kinases, thereby targeting them for degradation. They contain a phosphotyrosine-binding region, comprising an EF-hand and an SH2 domain, linked to an E3 ubiquitin-ligase domain. CblA, a Dictyostelium homologue of the Cbl proteins, contains all three conserved domains.

Evidence that DIF-1 and hyper-osmotic stress activate a Dictyostelium STAT by inhibiting a specific protein tyrosine phosphatase.

STATc becomes tyrosine phosphorylated and accumulates in the nucleus when Dictyostelium cells are exposed to the prestalk cell inducer Differentiation inducing factor 1 (DIF-1), or are subjected to hyper-osmotic stress. We show that the protein tyrosine phosphatase PTP3 interacts directly with STATc and that STATc is refractory to activation in PTP3 overexpressing cells. Conversely, overexpression of a dominant inhibitor of PTP3 leads to constitutive tyrosine phosphorylation and ectopic nuclear localisation of STATc.

Rapid generation of gene disruption constructs by in vitro transposition and identification of a Dictyostelium protein kinase that regulates its rate of growth and development.

We describe a rapid method for creating Dictyo stelium gene disruption constructs, whereby the target gene is interrupted by a drug resistance cassette using in vitro transposition. A fragment of genomic DNA containing the gene to be disrupted is amplified by PCR, cloned into a plasmid vector using topoisomerase and then employed as the substrate in an in vitro Tn5 transposition reaction. The transposing species is a fragment of DNA containing a Dictyostelium blasticidin S resistance (bs(r)) cassette linked to a bacterial tetracycline resistance (tet(r)) cassette.