Definition - What does Maternal mRNA mean?
Maternal mRNA (messenger ribonucleic acid) is a molecule which carries genetic information, specifically from the maternal genome which can be found in the egg.
The formation of maternal mRNA begins in oogenesis, and it remains translationally inactive until the sperm fertilizes the egg. It then becomes the driving factor for the earliest steps in embryonic development.
FertilitySmarts explains Maternal mRNA
Maternal mRNA is extremely important because it regulates many different processes which are necessary for both its development and that of the early embryo. One the egg is fertilized, the zygote relies exclusively on maternal mRNA for its development until its own genome is activated.
Fertilization acts as a trigger which signals a cascade of events, one of which is the immediate translation of the maternal mRNA into protein. These changes govern the beginning of cleavage all the way through to the blastula stage.
Although both the male and female contribute to the chromosomal content, the egg plays a crucial role in many of the initial processes. The maternal mRNA will eventually be degraded when control switches over from the maternal mRNA to the zygote in what is called the maternal-to-zygotic transition (MZT).
For the first time, both the paternal and maternal genomes are utilized in combination and embryogenesis can proceed as usual.