WordNet

(genetics) the diploid cell resulting from the union of a haploid spermatozoon and ovum (including the organism that develops from that cell) (同)fertilized_ovum
undergo conjugation
unite chemically so that the product is easily broken down into the original compounds
formed by the union of two compounds; "a conjugated protein" (同)conjugated
of an organic compound; containing two or more double bonds each separated from the other by a single bond (同)conjugated
joined together especially in a pair or pairs (同)conjugated, coupled
(of a pinnate leaflet) having only one pair of leaflets
add inflections showing person, number, gender, tense, aspect, etc.; "conjugate the verb"
of or relating to a zygote
(genetics) an organism having two different alleles of a particular gene and so giving rise to varying offspring
the second stage of the prophase of meiosis

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〈動詞〉'を'活用(変化)させる / 〈動詞が〉活用(変化)する / 〈単細胞生物が〉接合する / (特に対になって)結合した,接合の

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出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2014/10/06 19:44:43」(JST)

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A zygote (from Greek ζυγωτός zygōtos "joined" or "yoked", from ζυγοῦν zygoun "to join" or "to yoke"),^[1] is the initial cell formed when two gamete cells are joined by means of sexual reproduction. In multicellular organisms, it is the earliest developmental stage of the embryo. In single-celled organisms, the zygote divides to produce offspring, usually through mitosis, the process of cell division.

In multicellular organisms, a zygote is always synthesized from the union of two gametes, and constitutes the first stage in a unique organism's development. Zygotes are usually produced by a fertilization event between two haploid cells—an ovum (female gamete) and a sperm cell (male gamete)—which combine to form the single diploid cell. Such zygotes contain DNA derived from both parents, and this provides all the genetic information necessary to form a new individual. In land plants, the zygote is formed within a chamber called the archegonium. In seedless plants, the archegonium is usually flask-shaped, with a long hollow neck through which the sperm cell enters. As the zygote divides and grows, it does so inside the archegonium. With onset of the first cellular divisions, an animal zygote transforms into a morula, or a mass of cells.

Oscar Hertwig and Richard Hertwig made some of the first discoveries on the zygote formation.

Animals

In animal development, the term zygote is also used more loosely to refer to the group of cells formed by the first few cell divisions, although this is properly referred to as a morula.^[2]

In mammalian reproduction, after fertilization has taken place the zygote travels down the fallopian tube, while dividing to form more cells^[3] without the zygote actually increasing in size. This cell division is mitotic, and is known as cleavage.^[4] All mammals go through the zygote stage of life. Mammalian zygotes eventually develop into a blastocyst, after which they are more generally termed an embryo, and then a fetus.

A human zygote exists as a single cell before undergoing cleavage, forming blastomeres,^[5] and becomes a blastocyst on the fifth day.^[6]

In other species

A biparental zygote is a Chlamydomonas (a kind of algae) zygote that contains chloroplast DNA (cpDNA) from both parents.

References

^ "English etymology of zygote". myetymology.com.
^ Neas, John F. "Human Development". Embryology Atlas
^ O’Reilly, Deirdre. "Fetal development". MedlinePlus Medical Encyclopedia (2007-10-19). Retrieved 2009-02-15.
^ Klossner, N. Jayne and Hatfield, Nancy. Introductory Maternity & Pediatric Nursing, p. 107 (Lippincott Williams & Wilkins, 2006).
^ Blastomere Encyclopædia Britannica. Encyclopædia Britannica Online. Encyclopædia Britannica Inc., 2012. Web. 06 Feb. 2012.
^ Blackburn, Susan. Maternal, Fetal, & Neonatal Physiology, p. 80 (Elsevier Health Sciences 2007).

Preceded by Oocyte + Sperm	Stages of human development Zygote	Succeeded by Embryo

UpToDate Contents

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1. Evaluation of and initial approach to the adult patient with undifferentiated hypotension and shock
2. 頸動脈内膜剥離術および頸動脈ステント留置術の麻酔 anesthesia for carotid endarterectomy and carotid stenting
3. 静脈血栓塞栓症の患者における理論的根拠と無期限の抗凝固の適応 rationale and indications for indefinite anticoagulation in patients with venous thromboembolism
4. 中枢型睡眠無呼吸症候群を有する成人患者における陽圧呼吸調整法のモード選択 mode selection for positive airway pressure titration in adult patients with central sleep apnea syndromes
5. 胸部子宮内膜症：病因、疫学、および病理 thoracic endometriosis pathogenesis epidemiology and pathology

English Journal

Oct4 is required for lineage priming in the developing inner cell mass of the mouse blastocyst.

Le Bin GC1, Muñoz-Descalzo S, Kurowski A, Leitch H, Lou X, Mansfield W, Etienne-Dumeau C, Grabole N, Mulas C, Niwa H, Hadjantonakis AK, Nichols J.Author information 1Wellcome Trust - Medical Research Council Cambridge Stem Cell Institute, University of Cambridge, Tennis Court Road, Cambridge CB2 1QR, UK.AbstractThe transcription factor Oct4 is required in vitro for establishment and maintenance of embryonic stem cells and for reprogramming somatic cells to pluripotency. In vivo, it prevents the ectopic differentiation of early embryos into trophoblast. Here, we further explore the role of Oct4 in blastocyst formation and specification of epiblast versus primitive endoderm lineages using conditional genetic deletion. Experiments involving mouse embryos deficient for both maternal and zygotic Oct4 suggest that it is dispensable for zygote formation, early cleavage and activation of Nanog expression. Nanog protein is significantly elevated in the presumptive inner cell mass of Oct4 null embryos, suggesting an unexpected role for Oct4 in attenuating the level of Nanog, which might be significant for priming differentiation during epiblast maturation. Induced deletion of Oct4 during the morula to blastocyst transition disrupts the ability of inner cell mass cells to adopt lineage-specific identity and acquire the molecular profile characteristic of either epiblast or primitive endoderm. Sox17, a marker of primitive endoderm, is not detected following prolonged culture of such embryos, but can be rescued by provision of exogenous FGF4. Interestingly, functional primitive endoderm can be rescued in Oct4-deficient embryos in embryonic stem cell complementation assays, but only if the host embryos are at the pre-blastocyst stage. We conclude that cell fate decisions within the inner cell mass are dependent upon Oct4 and that Oct4 is not cell-autonomously required for the differentiation of primitive endoderm derivatives, as long as an appropriate developmental environment is established.
Development (Cambridge, England).Development.2014 Mar;141(5):1001-10. doi: 10.1242/dev.096875. Epub 2014 Feb 6.
The transcription factor Oct4 is required in vitro for establishment and maintenance of embryonic stem cells and for reprogramming somatic cells to pluripotency. In vivo, it prevents the ectopic differentiation of early embryos into trophoblast. Here, we further explore the role of Oct4 in blastocys
PMID 24504341

Identification of Suppressors of mbk-2/DYRK by Whole-Genome Sequencing.

Wang Y1, Wang JT, Rasoloson D, Stitzel ML, O' Connell KF, Smith HE, Seydoux G.Author information 1Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205.AbstractScreening for suppressor mutations is a powerful method to isolate genes that function in a common pathway or process. Because suppressor mutations often do not have phenotypes on their own, cloning of suppressor loci can be challenging. A method combining whole-genome sequencing (WGS) and single nucleotide polymorphism (SNP) mapping (WGS/SNP mapping) was developed to identify mutations with visible phenotypes in C. elegans. We show here that WGS/SNP mapping is an efficient method to map suppressor mutations without the need for previous phenotypic characterization. Using RNA-mediated interference to test candidate loci identified by WGS/SNP mapping, we identified 10 extragenic and six intragenic suppressors of mbk-2, a DYRK family kinase required for the transition from oocyte to zygote. Remarkably, seven suppressors are mutations in cell-cycle regulators that extend the timing of the oocyte-to-zygote transition.
G3 (Bethesda, Md.).G3 (Bethesda).2014 Feb 19;4(2):231-241. doi: 10.1534/g3.113.009126.
Screening for suppressor mutations is a powerful method to isolate genes that function in a common pathway or process. Because suppressor mutations often do not have phenotypes on their own, cloning of suppressor loci can be challenging. A method combining whole-genome sequencing (WGS) and single nu
PMID 24347622

Embryonic Development of Cuban Gar (Atractosteus tristoechus) Under Laboratory Conditions.

Comabella Y1, Canabal J, Hurtado A, García-Galano T.Author information 1Centro de Investigaciones Marinas, Universidad de la Habana, Calle 16 # 114 e/1ra y 3ra, Miramar, Playa, Cuba.AbstractThe embryonic development of Cuban gar (Atractosteus tristoechus) was described under controlled laboratory conditions. During the whole embryogenesis seven periods were defined: the zygote (0-½ h), cleavage (¾-4 h), blastula (5-10 h), gastrula (12-20 h), segmentation (24-40 h), pharyngula (48-66 h) and hatching (72-96 h) periods. The stages were based on morphological features, generally readily identified by examination of the embryo with the dissecting stereomicroscope. Hatching occurred 96 ± 4 h after spawning at 28°C.
Anatomia, histologia, embryologia.Anat Histol Embryol.2014 Feb 14. doi: 10.1111/ahe.12101. [Epub ahead of print]
The embryonic development of Cuban gar (Atractosteus tristoechus) was described under controlled laboratory conditions. During the whole embryogenesis seven periods were defined: the zygote (0-½ h), cleavage (¾-4 h), blastula (5-10 h), gastrula (12-20 h), segmentation (24-40 h), pharyngula (4
PMID 24527771

Japanese Journal

Studies on conjugation of Spirogyra using monoclonal culture

Ikegaya Hisato,Nakase Takuto,Iwata Kazuyoshi [他]
Journal of plant research 125(3), 457-464, 2012-05
NAID 40019242683

Unusual coelom formation in the direct-type developing sand dollar Peronella japonica

Tsuchimoto Jun,Yamada Toshihiro,Yamaguchi Masaaki
Developmental Dynamics 240(11), 2432-2439, 2011-11
… Peronella japonica is a sand dollar with a zygote that develops into an abbreviated pluteus but then metamorphoses on day three. …
NAID 120003459666

Related Pictures

★リンクテーブル★

リンク元	「ヘテロ接合性欠失」「conjugate」「配偶子」「zygotic」「fertilized egg」
拡張検索	「zygotene stage」「zygote nuclei」「zygote nucleus」

「ヘテロ接合性欠失」

Zygote
Gray's	p.45
Days	0
Precursor	Gametes
Gives rise to	Morula
Code	TE E2.0.1.2.0.0.9

　　[★]

英: loss of heterozygosity LOH, allelic loss
同: ヘテロ接合性欠損、ヘテロ接合性喪失
関

参考1

Loss of heterozygosity (LOH) in a cell represents the loss of normal function of one allele of a gene in which the other allele was already inactivated. This term is mostly used in the context of oncogenesis; after an inactivating mutation in one allele of a tumor suppressor gene occurs in the parent's germline cell, it is passed on to the zygote resulting in an offspring that is heterozygous for that allele. In oncology, loss of heterozygosity occurs when the remaining functional allele in a somatic cell of the offspring becomes inactivated by mutation. This results in no normal tumor suppressor being produced and this could result in tumorigenesis.