In some cases, special structures, such

as a haustorium or an arbuscle, are formed in host cells for the symbiont to absorb nutrition [22, 23]. To describe invasive growth, 15 new GO terms were developed that are children or lower level offspring of “”GO ID 0044412 growth or development of symbiont within host”". The term “”GO ID 0075065 growth or development of symbiont in host cell”" has two children, “”GO ID 0052094 formation by symbiont of haustorium for nutrient acquisition from host”" and “”GO ID 0075066 growth or development of symbiont in host organelle”". Additionally, arbuscules produced by mycorrhizal fungi are a type of structure functionally similar to haustoria, and thus “”GO ID 0075328 formation by symbiont of arbuscule for nutrient acquisition from host”" is a sibling of “”GO ID 0052094″” (see MK-2206 mw details in Figure 4). The 15 new GO terms in this section meet the need to annotate pathogen genes that are involved AZD6738 nmr in invasive growth. For example, the MST12 gene in the rice blast fungus M. grisea was found to regulate infectious growth but not appressorium formation [46]. In particular, no obvious defects in vegetative growth, conidiation, or conidia germination were observed in MST12 deletion mutants. Also, MST12 mutants produce typical dome-shaped

and melanized appressoria. When inoculated through wound sites, MST12 mutants fail to cause spreading lesions and appear to be defective in infectious growth. As a result, MST12 mutants are nonpathogenic [46]. Thus, the MST12 gene can be annotated with the term “”GO ID 0075061 formation of symbiont invasive hypha within host”". Lesion development Liothyronine Sodium in the host The eventual result of infection in most cases is lesion development. A lesion can be defined as any abnormality involving any tissue or organ due to any disease or any injury (cited from MedicineNet.com). Not

surprisingly, there are many types of lesions including those caused by damage such as cold injury or insects’ bites etc. It is difficult to define lesions objectively, as this requires a subjective judgment on what constitutes abnormal or damage and from what perspective, ranging for example from perturbation of a few cells to death of an entire tissue or organ. Similarly, formation of a lesion is not a specific process belonging to either the pathogen or the host and can be highly dependent on the environment. Therefore, at this time only one term, “”GO ID 0009405 pathogenesis”", is appropriate for genes involved in lesion formation. Other new GO terms Six new terms were placed jointly under the nodes “”GO ID 0006914 autophagy”" and “”GO ID 0044403 symbiosis, encompassing mutualism through parasitism”".