Nlrp5, a maternal-effect gene, is crucial for normal pre-implantation and embryonic development [1,2,4,5,7,8]. It is part of the subcortical maternal complex (SCMC) and may be involved in stabilizing UHRF1 protein in the cytoplasm, which is relevant to maintaining CpG methylation of imprinting control regions during pre-implantation development [3].

In mouse models, Nlrp5 mutant oocytes have abnormal mitochondrial localization and increased activity, leading to reactive oxygen species accumulation, mitochondrial depletion, and early embryonic arrest at the two-cell stage. In sows, knockdown of NLRP5 arrests early embryogenesis [7,8]. In humans, mutations in NLRP5 are associated with female infertility, including oocyte maturation abnormality, total fertilization failure, and early embryonic arrest [2,5,9]. In sheep, certain mutations in NLRP5 are associated with litter size [6].

In conclusion, Nlrp5 plays an essential role in early embryogenesis across different species. Studies using gene-knockout or knockdown models in mice and sows, along with human genetic studies, have revealed its significance in processes like mitochondrial function regulation in oocytes and embryos, and its mutations are linked to infertility-related diseases.