The antigens recognized by 3 anti synaptonemal complex protein antibodies are specific to the meiotic prophase

In the rat ovary, germ and somatic cells become organized into primordial follicles 48–72 h after birth. Although several genes have been implicated in the control of early follicular growth, less is known about the factors involved in the formation of primordial follicles. Using the method of differential display of mRNAs, we found several genes differentially expressed at the time of follicular assembly. One of them encodes synaptonemal complex protein-1 (SCP1), a core component of the protein complex that maintains recombining chromosomes together during prophase I of the first meiotic division in germ cells. This association, evident during the pachytene stage, ends when chromosomal desynapsis begins in the diplotene stage at the end of prophase I. Oocytes become arrested in the diplotene/dictate stage before becoming enclosed into primordial follicles, suggesting that oocytes must complete meiotic prophase I before becoming competent to direct follicle assembly. We now show that attainment of the diplotene stage results in follicular formation. In developing rat ovaries, SCP1 mRNA expression is confined to oocytes and decreases precipitously within 24 h after birth, preceding the organization of primordial follicles. The premature loss of SCP1, achieved via treatment with an antisense oligodeoxynucleotide targeting SCP1 mRNA, resulted in more oocytes reaching the diplotene stage, as evidenced by a decrease in the number of oocytes containing germ cell nuclear antigen-1 (a nuclear protein whose expression ceases in diplotene) and an increase in the number of oocytes expressing MSY2 (a cytoplasmic Y box protein expressed in oocytes that have become arrested in diplotene). SCP1-deficient ovaries exhibited an increased number of newly formed follicles, suggesting that completion of meiotic prophase I endows oocytes with the ability to orchestrate follicular assembly.

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Phosphorylation of the synaptonemal complex protein SYP-1 promotes meiotic chromosome segregation

10.1101/211672 ◽

2017 ◽

Cited By ~ 1

Author(s):

Aya Sato-Carlton ◽

Chihiro Nakamura-Tabuchi ◽

Stephane Kazuki Chartrand ◽

Tomoki Uchino ◽

Peter Mark Carlton

Keyword(s):

Synaptonemal Complex ◽

Meiotic Chromosome ◽

C Elegans ◽

Chromosome Domains ◽

Chromatid Cohesion ◽

Complex Protein ◽

Chromosomal Passenger ◽

Synaptonemal Complex Protein ◽

A Site ◽

Meiosis I

AbstractChromosomes that have undergone crossing-over in meiotic prophase must maintain sister chromatid cohesion somewhere along their length between the first and second meiotic divisions. While many eukaryotes use the centromere as a site to maintain cohesion, the holocentric organism C. elegans instead creates two chromosome domains of unequal length termed the short arm and long arm, which become the first and second site of cohesion loss at meiosis I and II. The mechanisms that confer distinct functions to the short and long arm domains remain poorly understood. Here, we show that phosphorylation of the synaptonemal complex protein SYP-1 is required to create these domains. Once crossovers are made, phosphorylated SYP-1 and PLK-2 become cooperatively confined to short arms and guide phosphorylated histone H3 and the chromosomal passenger complex to the site of meiosis I cohesion loss. Our results show that PLK-2 and phosphorylated SYP-1 ensure creation of the short arm subdomain, promoting disjunction of chromosomes in meiosis I.

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X-ray crystallographic studies of the middle part of the human synaptonemal complex protein 1 coiled-coil domain

Acta Crystallographica Section F Structural Biology Communications ◽

10.1107/s2053230x15012728 ◽

2015 ◽

Vol 71 (9) ◽

pp. 1131-1134 ◽

Cited By ~ 1

Author(s):

Hyun Ho Park

Keyword(s):

Synaptonemal Complex ◽

Short Form ◽

Complex Structure ◽

Coiled Coil ◽

Middle Part ◽

X Ray ◽

Cell Parameters ◽

Coiled Coil Domain ◽

Complex Protein ◽

Synaptonemal Complex Protein

The synaptonemal complex is a meiosis-specific complex structure formed at the synapse of homologous chromosomes to hold them together during meiosis. Synaptonemal complex protein 1 (SYCP1) is one of the components of the syneptonemal complex. In this study, the short form of the coiled-coil domain of SYCP1 was overexpressed inEscherichia coliwith an engineered C-terminal His tag. The short form of the coiled-coil domain of SYCP1 was then purified to homogeneity and crystallized at 293 K. X-ray diffraction data were collected to a resolution of 3.0 Å from a crystal belonging to space groupI4, with unit-cell parametersa= 41.95,b= 41.95,c= 318.78 Å. The asymmetric unit was estimated to contain two molecules.

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