Genipa americana L., commonly known as genipap, belongs to the Rubiaceae family. This study aimed describe pollen morphology of species, evaluate its meiotic behavior and viability, provide information help maintenance conservation species in natural habitat. Flower buds were collected from 20 individuals Alta Floresta Matupá municipalities, Mato Grosso, Brazil. Pollen was characterized using a...

Chromosome segregation during meiosis in oocytes is error prone. The uniquely large cytoplasmic size of oocytes, which provides support for embryogenesis after fertilization, might be a predisposing factor for meiotic errors. However, this hypothesis remains unproven. Here, we show that cytoplasmic size affects the functionality of the acentrosomal spindle. Artificially decreasing the cytoplasm...

cAMP plays a critical role in the control of oocyte maturation, as a high level of cAMP maintains oocyte arrest at the first meiotic prophase. Yet this study shows that pulsing meiotically arrested denuded oocytes (DO) with cAMP induces oocyte maturation through the activation of AMP-activated protein kinase (PRKA). Short-term (3 h) pulsing of meiotically arrested oocytes with forskolin, an ade...

We have previously shown that fatty acid oxidation (FAO) is required for AMP-activated protein kinase (PRKA)-induced maturation in vitro. In the present study, we have further investigated the role of this metabolic pathway in hormone-induced meiotic maturation. Incorporating an assay with (3)H-palmitic acid as the substrate, we first examined the effect of PRKA activators on FAO levels. There ...

A cytogenetical study on 13 alfalfa (Medicago sativa) cultivars available in Iranian Forest and Rangelands Genebank was performed in order to obtain basic information on the variability in chiasma frequency/distribution, chromosome association and segregation. Such cytogenetic information is useful for planning hybridization programs. Cluster analysis of meiotic data and ordination of cultivars...

in the present paper, the cytogenetic study including meiotic chromosome number and behavior along with pollen viability were performed in 4 populations of trigonella spruneriana boiss. this is the first cytogenetic report of the taxon. all populations are diploid and possess 2n = 2x = 16 chromosome number, which is consistent with the proposed basic number of x = 8. in addition, some meiotic i...

BACKGROUND In spite of extensive efforts to improve in vitro oocyte maturation, the obtained results are not very efficient. This study was conducted to assess impacts of cAMP elevating agents and alpha lipoic acid (ALA) on in vitro oocyte maturation and fertilization. METHODS Mouse germinal vesicle (GV) oocytes were categorized into cumulus denuded oocytes (DOs; n=896) and cumulus oocyte com...