Dear Editor, Tumor necrosis factor （TNF） family ligands in vertebrates are type Ii transmembrane proteins with functions in the regulation of immunity, bone homeostasis and more [1]. Drosophila expresses a single TN...Dear Editor, Tumor necrosis factor （TNF） family ligands in vertebrates are type Ii transmembrane proteins with functions in the regulation of immunity, bone homeostasis and more [1]. Drosophila expresses a single TNF homologue, Eiger [2, 3], which contains in addition to the homotrimeric C-terminal TNF homology domain （THD） an extended extracellular portion harboring potential pro- tease cleavage sites （Figure 1A-i）. One of these sites （Val 145） was identified experimentally [4]. A second potential cleavage site （Arg 211） resembling a canonical furin consensus sequence （R-K-S-R compared to R-X-R/K-R） was cleaved by a furin-like activity when expressed in mammalian 293T cells （Supplementary information, Figure S1）. Eiger modulates host responses to Salmonella infections and resistance against extracellular pathogens in Drosophila [5, 6]. When expressed in the eye, it induces cell death via a well-defined pathway （Figure 1 B） [2, 3, 7]. The structural requirements for Eiger＇s activity are however unknown.展开更多
文摘Dear Editor, Tumor necrosis factor （TNF） family ligands in vertebrates are type Ii transmembrane proteins with functions in the regulation of immunity, bone homeostasis and more [1]. Drosophila expresses a single TNF homologue, Eiger [2, 3], which contains in addition to the homotrimeric C-terminal TNF homology domain （THD） an extended extracellular portion harboring potential pro- tease cleavage sites （Figure 1A-i）. One of these sites （Val 145） was identified experimentally [4]. A second potential cleavage site （Arg 211） resembling a canonical furin consensus sequence （R-K-S-R compared to R-X-R/K-R） was cleaved by a furin-like activity when expressed in mammalian 293T cells （Supplementary information, Figure S1）. Eiger modulates host responses to Salmonella infections and resistance against extracellular pathogens in Drosophila [5, 6]. When expressed in the eye, it induces cell death via a well-defined pathway （Figure 1 B） [2, 3, 7]. The structural requirements for Eiger＇s activity are however unknown.
