pronucleus


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Related to pronucleus: Female pronucleus

pronucleus

 [pro-noo´kle-us]
the haploid nucleus of a germ cell.
female pronucleus the haploid nucleus of the fully mature oocyte, which loses its nuclear envelope and liberates its chromosomes to meet the synapsis with those from the male pronucleus.
male pronucleus the nuclear material of the head of a spermatozoon, after it has penetrated the oocyte and acquired a pronuclear membrane.

pro·nu·cle·us

, pl.

pro·nu·cle·i

(prō-nū'klē-ŭs, -klē-ī),
1. One of a pair of nuclei undergoing fusion in karyogamy.
2. In embryology, the nuclear material of the head of the sperm (male pronucleus) or of the oocyte (female pronucleus), after the oocyte has been penetrated by the sperm; each pronucleus normally carries a haploid set of chromosomes, so that the merging of the pronuclei in fertilization reestablishes diploidy.

pronucleus

/pro·nu·cle·us/ (-noo´kle-us)
1. the precursor of a nucleus.
2. the haploid nucleus occurring after meiosis in a germ cell.

pronucleus

(prō-no͞o′klē-əs, -nyo͞o′-)
n. pl. pronu·clei (-klē-ī′)
The haploid nucleus of a sperm or egg before fusion of the nuclei in fertilization.

pro·nu′cle·ar adj.

pronucleus

[-no̅o̅′klē·əs] pl. pronuclei
Etymology: Gk, pro + L, nucleus, nut kernel
the nucleus of an ovum or a spermatozoon after fertilization but before fusion of the chromosomes to form the nucleus of the zygote. Each pronucleus contains the haploid number of chromosomes, is larger than the normal nucleus, and is diffuse in appearance. The pronucleus of the ovum is formed only after it has completed its second meiotic division and the second polar body has formed, which occur after the spermatozoon has penetrated. It then loses its nuclear envelope, releasing the chromosomes so that synapsis with the chromosomes of the male pronucleus, which is contained in the head of the spermatozoon, can occur. Also called germinal nucleus, germ nucleus. See also oogenesis, spermatogenesis.

pro·nu·cle·us

, pl. pronuclei (prō-nū'klē-ŭs, -ī)
1. One of a pair of nuclei undergoing fusion in karyogamy.
2. embryology The nuclear material of the head of the sperm (male pronucleus) or of the oocyte (female pronucleus), after the oocyte has been penetrated by the sperm; each pronucleus normally carries a haploid set of chromosomes, so that the merging of the pronuclei in fertilization reestablishes the diploidy.

pronucleus

pl. pronuclei; the haploid nucleus of a sex cell.

female pronucleus
the haploid nucleus of the fully mature ovum which loses its nuclear envelope and liberates its chromosomes to meet the synapsis with those from the male pronucleus.
male pronucleus
the nuclear material of the head of a spermatozoon, after it has penetrated the ovum and acquired a pronuclear membrane.
References in periodicals archive ?
Mouse zygotes with one diploid pronucleus formed as a result of ICSI can develop normally beyond birth.
In this experimental condition, the majority of injected oocytes failed to form the male pronucleus and had intact, decondensed or swelled sperm heads (Figures 2A-C).
Even if we insist that some central control is present in the hydatidiform mole--a possibility that makes more sense, perhaps, in the hydatidiform mole that suffers from polyspermy, since the presence of the maternal pronucleus allows for the possibility of the development of the body of the embryo proper--we would have to note that this controller is profoundly defective, so that the developing organism is doomed to die.
Furthermore, in patients with single pronucleus and no pronuclei appropriately-cleaved embryos, the rate of aneuploidy was high enough to label the embryos as abnormal from the outset.
Interestingly, the number of oocytes presenting a pronucleus (PN) formation using sperm from boar 2012 was only four, one oocyte had 1PN and 3 oocytes had 2PN.
After the 4 hr incubation for fertilization and the following 3 hr of culture in fresh medium, zygotes were evaluated for pronucleus formation by using an inverted microscope.
Ca2+ oscillation-inducing phospholipase C zeta expressed in mouse eggs is accumulated to the pronucleus during egg activation.
Cysteamine is a thiol that increased GSH and promoted male pronucleus formation in porcine oocyte.
This method involves transfer of a desired gene construct from same species or from a different species into the pronucleus of a reproductive cell.
In addition, the cytological studies revealed that the donor sperm incorporated into the egg cytoplasm, developed into the male pronucleus, and merged with the female pronucleus eventually in some interspecific crosses in molluscs, such as C.
Therefore, the oocytes would go directly into interphase and only one diploid pronucleus would be formed (19).
Of these, ds DNA breaks are the most mutagenic, because in the pronucleus stage zygote, the two genomes are separated, hence DNA template information for error free repair of the ds breaks is absent.