NLRPs, the subcortical maternal complex and genomic imprinting

Area of Science:

• Reproductive biology
• Genomic imprinting
• Maternal effect genes

Background:

• Oocytes supply essential RNAs and proteins for embryonic epigenetic reprogramming and totipotency.
• Oocyte-derived transcripts, particularly those in the subcortical maternal complex (SCMC), are vital for early development.
• Mutations in human maternal-effect genes (NLRP7, KHDC3L, NLRP5) cause reproductive anomalies like biparental hydatidiform moles (BiHM).

Purpose of the Study:

• To review the roles of NLRP family members and SCMC proteins in mammalian reproduction.
• To discuss the establishment of genomic imprints and post-zygotic methylation maintenance.
• To summarize recent advances in understanding BiHM formation and SCMC functions.

Main Methods:

• Review of existing literature on maternal-effect genes, SCMC, genomic imprinting, and BiHM.
• Analysis of genetic and biochemical studies implicating NLRP genes and SCMC proteins.
• Discussion of findings from targeted transcript disruption in mice models.

Main Results:

• Targeted disruption of oocyte-derived transcripts causes embryonic lethality and developmental arrest.
• Maternal mutations in NLRP7, KHDC3L, and NLRP5 are linked to reproductive issues and imprinting disturbances.
• SCMC members and interacting partners play critical roles in early development and imprinting.

Conclusions:

• The SCMC and related maternal factors are essential for successful mammalian reproduction.
• Understanding these factors is key to addressing reproductive failures like BiHM.
• Further research is needed to elucidate the precise mechanisms of SCMC action in imprinting and development.