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Biochemical isolation and purification of ovulation-inducing factor (OIF) in seminal plasma of llamas

BACKGROUND: The objective of the present study was to isolate and purify the protein fraction(s) of llama seminal plasma responsible for the ovulation-inducing effect of the ejaculate. METHODS: Semen collected from male llamas by artificial vagina was centrifuged and the seminal plasma was harvested...

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Autores principales: Ratto, Marcelo H, Delbaere, Louis TJ, Leduc, Yvonne A, Pierson, Roger A, Adams, Gregg P
Formato: Texto
Lenguaje:English
Publicado: BioMed Central 2011
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3050803/
https://www.ncbi.nlm.nih.gov/pubmed/21310078
http://dx.doi.org/10.1186/1477-7827-9-24
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author Ratto, Marcelo H
Delbaere, Louis TJ
Leduc, Yvonne A
Pierson, Roger A
Adams, Gregg P
author_facet Ratto, Marcelo H
Delbaere, Louis TJ
Leduc, Yvonne A
Pierson, Roger A
Adams, Gregg P
author_sort Ratto, Marcelo H
collection PubMed
description BACKGROUND: The objective of the present study was to isolate and purify the protein fraction(s) of llama seminal plasma responsible for the ovulation-inducing effect of the ejaculate. METHODS: Semen collected from male llamas by artificial vagina was centrifuged and the seminal plasma was harvested and stored frozen. Seminal plasma was thawed and loaded onto a Type 1 macro-prep ceramic hydroxylapatite column and elution was carried out using a lineal gradient with 350 mM sodium phosphate. Three protein fractions were identified clearly (Fractions A, B, and C), where a prominent protein band with a mass of 14 kDa was identified in Fraction C. Fraction C was loaded into a sephacryl gel filtration column for further purification using fast protein liquid chromatography (FPLC). Isocratic elution resulted in 2 distinct protein fractions (Fractions C1 and C2). An in vivo bioassay (n = 10 to 11 llamas per group) was used to determine the ovarian effect of each fraction involving treatment with saline (negative control), whole seminal plasma (positive control), or seminal plasma Fractions A, B or C2. Ultrasonography was done to detect ovulation and CL formation, and blood samples were taken to measure plasma progesterone and LH concentrations. RESULTS: Ovulation and CL formation was detected in 0/10, 10/11, 0/10, 2/11, and 10/11 llamas treated with saline, whole seminal plasma, Fractions A, B and C2 respectively (P < 0.001). A surge in circulating concentrations of LH was detected within 2 hours only in llamas treated with either whole seminal plasma or Fraction C2. Plasma progesterone concentration and CL diameter profiles were greatest (P < 0.05) in llamas treated with Fraction C2. CONCLUSION: Ovulation-inducing factor was isolated from llama seminal plasma as a 14 kDa protein molecule that elicits a preovulatory LH surge followed by ovulation and CL formation in llamas, suggesting an endocrine effect at the level of the hypothalamus (release of GnRH) or the pituitary (gonadotrophs).
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spelling pubmed-30508032011-03-09 Biochemical isolation and purification of ovulation-inducing factor (OIF) in seminal plasma of llamas Ratto, Marcelo H Delbaere, Louis TJ Leduc, Yvonne A Pierson, Roger A Adams, Gregg P Reprod Biol Endocrinol Research BACKGROUND: The objective of the present study was to isolate and purify the protein fraction(s) of llama seminal plasma responsible for the ovulation-inducing effect of the ejaculate. METHODS: Semen collected from male llamas by artificial vagina was centrifuged and the seminal plasma was harvested and stored frozen. Seminal plasma was thawed and loaded onto a Type 1 macro-prep ceramic hydroxylapatite column and elution was carried out using a lineal gradient with 350 mM sodium phosphate. Three protein fractions were identified clearly (Fractions A, B, and C), where a prominent protein band with a mass of 14 kDa was identified in Fraction C. Fraction C was loaded into a sephacryl gel filtration column for further purification using fast protein liquid chromatography (FPLC). Isocratic elution resulted in 2 distinct protein fractions (Fractions C1 and C2). An in vivo bioassay (n = 10 to 11 llamas per group) was used to determine the ovarian effect of each fraction involving treatment with saline (negative control), whole seminal plasma (positive control), or seminal plasma Fractions A, B or C2. Ultrasonography was done to detect ovulation and CL formation, and blood samples were taken to measure plasma progesterone and LH concentrations. RESULTS: Ovulation and CL formation was detected in 0/10, 10/11, 0/10, 2/11, and 10/11 llamas treated with saline, whole seminal plasma, Fractions A, B and C2 respectively (P < 0.001). A surge in circulating concentrations of LH was detected within 2 hours only in llamas treated with either whole seminal plasma or Fraction C2. Plasma progesterone concentration and CL diameter profiles were greatest (P < 0.05) in llamas treated with Fraction C2. CONCLUSION: Ovulation-inducing factor was isolated from llama seminal plasma as a 14 kDa protein molecule that elicits a preovulatory LH surge followed by ovulation and CL formation in llamas, suggesting an endocrine effect at the level of the hypothalamus (release of GnRH) or the pituitary (gonadotrophs). BioMed Central 2011-02-10 /pmc/articles/PMC3050803/ /pubmed/21310078 http://dx.doi.org/10.1186/1477-7827-9-24 Text en Copyright ©2011 Ratto et al; licensee BioMed Central Ltd. http://creativecommons.org/licenses/by/2.0 This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
spellingShingle Research
Ratto, Marcelo H
Delbaere, Louis TJ
Leduc, Yvonne A
Pierson, Roger A
Adams, Gregg P
Biochemical isolation and purification of ovulation-inducing factor (OIF) in seminal plasma of llamas
title Biochemical isolation and purification of ovulation-inducing factor (OIF) in seminal plasma of llamas
title_full Biochemical isolation and purification of ovulation-inducing factor (OIF) in seminal plasma of llamas
title_fullStr Biochemical isolation and purification of ovulation-inducing factor (OIF) in seminal plasma of llamas
title_full_unstemmed Biochemical isolation and purification of ovulation-inducing factor (OIF) in seminal plasma of llamas
title_short Biochemical isolation and purification of ovulation-inducing factor (OIF) in seminal plasma of llamas
title_sort biochemical isolation and purification of ovulation-inducing factor (oif) in seminal plasma of llamas
topic Research
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3050803/
https://www.ncbi.nlm.nih.gov/pubmed/21310078
http://dx.doi.org/10.1186/1477-7827-9-24
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