Mokosh
Description
The Mokosh system was discovered in E. coli by examining clusters of genes enriched in defense islands (N/A) . It contains genes with an RNA helicase domain and a predicted phospholipase D domain (PLD) nuclease domain. Mutations in the ATP-binding domain of the helicase, and the active site of the PLD nuclease disrupt phage defense. The system is divided into two types. Mokosh type I has two genes, one gene containing the RNA helicase domain and an additional serine-threonine kinase domain (STK), and one gene containing the PLD nuclease. Type II Mokosh is formed of a single gene containing both the helicase and nuclease domains. Recent efforts have shown homology between the Mokosh system and human proteins involved in the piRNA pathway, a defense mechanism of animal germlines that prevents expression of transposable elements (N/A) . The system gets its name from the goddess protector of women's destiny in Slavic mythology (N/A) .
Molecular mechanisms
As far as we are aware, the molecular mechanism is unknown.
Example of genomic structure
A total of 7 subsystems have been described for the Mokosh system.
Here is some examples found in the RefSeq database:
The Mokosh_TypeII system in Massilia sp. NP310 (GCF_019443485.1, NZ_CP080379) is composed of 1 protein: MkoC (WP_184237977.1)
The Mokosh_Type_I_A system in Cupriavidus pauculus (GCF_019931045.1, NZ_CP082863) is composed of 2 proteins MkoA_A (WP_170292610.1) MkoB_A (WP_150981546.1)
The Mokosh_Type_I_B system in Collimonas pratensis (GCF_001584185.1, NZ_CP013234) is composed of 2 proteins MkoB_B (WP_061945389.1) MkoA_B (WP_061945390.1)
The Mokosh_Type_I_C system in Klebsiella sp. WP7-S18-CRE-02 (GCF_014169515.1, NZ_AP022189) is composed of 2 proteins MkoB_C (WP_227674162.1) MkoA_C (WP_227674163.1)
The Mokosh_Type_I_D system in Geomonas paludis (GCF_023221575.1, NZ_CP096574) is composed of 2 proteins MkoA_D (WP_248647094.1) MkoB_D (WP_248647095.1)
The Mokosh_Type_I_E system in Planococcus faecalis (GCF_002009235.1, NZ_CP019401) is composed of 2 proteins MkoA_E (WP_078080177.1) MkoB_E (WP_071154541.1)
Distribution of the system among prokaryotes
Structure
Group | Structure | Foldseek | System | Gene name | Subtype | Proteins in structure | System genes | Prediction type | N genes in sys | pLDDT | iptm+ptm | pDockQ |
---|---|---|---|---|---|---|---|---|---|---|---|---|
No data available |