| 1. |
- Barranco, Isabel, et al.
(författare)
-
Measurement of Activity and Concentration of Paraoxonase 1 (PON-1) in Seminal Plasma and Identification of PON-2 in the Sperm of Boar Ejaculates
- 2015
-
Ingår i: Molecular Reproduction and Development. - : Wiley-Blackwell. - 1040-452X .- 1098-2795. ; 82:1, s. 58-65
-
Tidskriftsartikel (refereegranskat)abstract
- This study revealed and characterised the presence of the antioxidant enzymes paraoxonase (PON) type 1 (PON-1, extracellular) and type 2 (PON-2, intracellular) in boar semen. To evaluate PON-1, an entire ejaculate from each of ten boars was collected and the seminal plasma was harvested after double centrifugation (1,500g for 10min). Seminal plasma was analysed for concentration as well as enzymatic activity of PON-1 and total cholesterol levels. Seminal-plasma PON-1 concentration ranged from 0.961 to 1.670ng/ml while its enzymatic activity ranged from 0.056 to 0.400 IU/ml, which represent individual variance. Seminal-plasma PON-1 concentration and enzymatic activity were negatively correlated (r=-0.763; Pless than0.01). The activity of seminal-plasma PON-1 negatively correlated with ejaculate volume (r=-0.726, Pless than0.05), but positively correlated with sperm concentration (r=0.654, Pless than0.05). Total seminal-plasma cholesterol concentration positively correlated with PON-1 activity (r=0.773; Pless than0.01), but negatively correlated with PON-1 concentration (r=-0.709; Pless than0.05). The presence of intracellular PON-2 was determined via immunocytochemistry in spermatozoa derived from artificial insemination. PON-2 localised to the post-acrosomal area of the sperm head and principal piece of the tail in membrane-intact spermatozoa. In summary, PON is present in boar semen, with PON-1 at low levels in seminal plasma and PON-2 within the spermatozoa. Further studies are needed to characterise the relationship between antioxidant PONs with sperm and other seminal-plasma parameters. Mol. Reprod. Dev. 82: 58-65, 2015. (c) 2014 Wiley Periodicals, Inc.
|
|
| 2. |
- Boija, Ann, et al.
(författare)
-
A Time of Change : Dynamics of Chromatin and Transcriptional Regulation During Nuclear Programming in Early Drosophila Development
- 2015
-
Ingår i: Molecular Reproduction and Development. - : Wiley. - 1040-452X .- 1098-2795. ; 82:10, s. 735-746
-
Forskningsöversikt (refereegranskat)abstract
- In order for a new organism to form, the genomes of the highly specialized egg and sperm need to be reprogrammed into a totipotent state that is capable of generating all of the cell types that comprise an organism. This reprogramming occurs by erasing chromatin modifications, leaving the cells in a naive state, followed by the induction of specialized programming events. Pioneer factors bind to the genome prior to zygotic genome activation, followed by acetylation of histones and further chromatin specialization by the addition of methylation marks later during differentiation. Genome-wide approaches have provided insight into the genomic and epigenomic regulation of gene expression during development, providing a new perspective on the process of cell specification and differentiation. In this review, we discuss how distal DNA and core promoter elements, RNA polymerase pausing, transcription factors, and co-regulators interact to shape the chromatin landscape and direct tissue-specific expression patterns during embryo development, focusing on the well-characterized Drosophila embryo.
|
|
| 3. |
|
|
| 4. |
- Cattelan, Silvia, et al.
(författare)
-
Differential gene regulation in selected lines for high and low sperm production in male guppies
- 2020
-
Ingår i: Molecular Reproduction and Development. - : Wiley. - 1040-452X .- 1098-2795. ; 87:4, s. 430-441
-
Tidskriftsartikel (refereegranskat)abstract
- In species where females mate with more than one male during the same reproductive event, males typically increase the number of sperm produced to boost their fertilization share. Sperm is not limitless, however, and theory predicts that their production will come at the cost of other fitness-related traits, such as body growth or immunocompetence, although these evolutionary trade-offs are notoriously difficult to highlight. To this end, we combined artificial selection for sperm production with a transcriptome analysis using Poecilia reticulata, a fish characterized by intense sperm competition in which the number of sperm transferred during mating is the most important predictor of fertilization success, yet sperm production is highly variable among males. We compared the brain and testes transcriptome in male guppies of lines artificially selected for high and low sperm production by identifying pivotal differentially expressed gene sets that may regulate spermatogenesis and immune function in this species. Despite the small differences in single genes' expression, gene set enrichment analysis showed coordinated gene expression differences associated with several pathways differentially regulated in the two selection lines. High sperm production males showed an upregulation of pathways related to immunosuppression and development of spermatozoa indicating a possible immunological cost of sperm production.
|
|
| 5. |
|
|
| 6. |
|
|
| 7. |
|
|
| 8. |
- Friberg, P. Anders, 1976, et al.
(författare)
-
Apoptotic effects of a progesterone receptor antagonist on rat granulosa cells are not mediated via reduced protein isoprenylation.
- 2007
-
Ingår i: Molecular reproduction and development. - : Wiley. - 1040-452X .- 1098-2795. ; 74:10, s. 1317-26
-
Tidskriftsartikel (refereegranskat)abstract
- Progesterone is a survival factor in rat periovulatory granulosa cells. The mechanisms involved are unclear but progesterone receptor (PGR) antagonists have been shown to inhibit cholesterol synthesis and induce apoptosis. Furthermore, reports suggest that statins induce apoptosis by inhibition of protein isoprenylation. Statins inhibit the rate-limiting step of the cholesterol synthesis, thereby reducing availability of intermediates used for the post-translational isoprenylation process. It has been suggested that PGR antagonists in a similar manner induce apoptosis by decreasing cholesterol synthesis and thereby protein isoprenylation. In this study we hypothesized that the mechanism by which the nuclear PGR antagonist Org 31,710 induces apoptosis in rat periovulatory granulosa cells, is by decreasing cholesterol synthesis and thereby general cell protein isoprenylation. Incubation of isolated granulosa cells with Org 31,710 or simvastatin for 22 hr resulted in increased apoptosis and reduced cholesterol synthesis. However, simvastatin caused a substantial inhibition of cholesterol synthesis after 6 hr in culture without inducing apoptosis. In contrast, Org 31,710 had only a modest effect on cholesterol synthesis after 6 hr while it significantly induced apoptosis. Addition of isoprenylation substrates partially reversed apoptosis induced by simvastatin and to a lesser extent apoptosis induced by Org 31,710. In addition, and in contrast to Org 31,710, simvastatin caused a decrease in isoprenylation of a selected isoprenylation marker protein, the Ras-related protein RAB11. In conclusion, we demonstrate that the PGR antagonist inhibits cholesterol synthesis in granulosa cells but reduced protein isoprenylation is not the mediating mechanism of increased apoptosis as previously hypothesized.
|
|
| 9. |
|
|
| 10. |
- Johannisson, Anders, et al.
(författare)
-
Oviductal fluid modulates the dynamics of tyrosine phosphorylation in cryopreserved boar spermatozoa during capacitation
- 2012
-
Ingår i: Molecular Reproduction and Development. - : Wiley. - 1040-452X .- 1098-2795. ; 79, s. 525-540
-
Tidskriftsartikel (refereegranskat)abstract
- Following insemination, spermatozoa are retained in the utero-tubal junction and isthmic region of the oviduct, where essential steps of capacitation are coordinated. Although a majority of the spermatozoa is exposed to similar conditions in the oviduct, the speed of the response varies depending on the individual male and the state of the spermatozoa. The present study evaluated individual boar variations in terms of the ability of spermatozoa to undergo tyrosine phosphorylation in response to isthmic oviductal fluid (ODF). Cryopreserved spermatozoa from four boars were incubated with pre- and post-ovulatory ODF for 6?hr. Sperm kinematics, global protein tyrosine phosphorylation, and dynamics of different phosphorylation patterns were analyzed at hourly interval. The percentage of phosphorylated spermatozoa in the pre-ovulatory ODF-treated group was significantly (P?
|
|
