Abstract
The union of haploid gametes at fertilization initiates the formation of the diploid zygote in sexually reproducing animals. This founding event of embryogenesis includes several fascinating cellular and nuclear processes, such as sperm–egg cellular interactions, sperm chromatin remodelling, centrosome formation or pronuclear migration. In comparison with other aspects of development, the exploration of animal fertilization at the functional level has remained so far relatively limited, even in classical model organisms. Here, we have reviewed our current knowledge of fertilization in Drosophila melanogaster, with a special emphasis on the genes involved in the complex transformation of the fertilizing sperm nucleus into a replicated set of paternal chromosomes.
Highlights
The vast majority of animals reproduce sexually through the union of two very different haploid gametes
The biology of fertilization has largely benefited from a small number of animal models for which eggs are available in relatively large quantities and fertilization can be controlled experimentally
We present in this article only a partial view of Drosophila fertilization, which is largely guided by the still limited number of functional studies that focus on this funding event of embryo development
Summary
The vast majority of animals reproduce sexually through the union of two very different haploid gametes. The biology of fertilization has largely benefited from a small number of animal models for which eggs are available in relatively large quantities and fertilization can be controlled experimentally These animals, which include marine invertebrates (essentially echinoderms and molluscs), as well as amphibians, were not amenable for genetic experimentations aimed at identifying factors required for the formation of a diploid zygote [1,2]. Fertilization in insects, and more generally in arthropods, belongs to the third type, called the gonomeric type In this case, pronuclei appose without fusing their envelopes, as in Ascaris, but the parental chromosomes remain separated until the end of the first zygotic mitosis [4]. The separation of parental chromosomes implies that any defect affecting one pronucleus does not necessarily prevent the unalduterated one to perform the first zygotic division within its own hemispindle When this occurs, the embryo is haploid and usually reaches late embryogenesis before arresting its development. We have reviewed the published literature relevant to the major steps of fertilization in Drosophila, from sperm entry to the first zygotic mitosis
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
