| Autor: |
Panda AP; Molecular Biology Laboratory, Indian Council of Agricultural Research-National Institute of Animal Nutrition and Physiology, Hosur Road, Adugodi, Bangalore 560030, Karnataka, India., Roy SC; Molecular Biology Laboratory, Indian Council of Agricultural Research-National Institute of Animal Nutrition and Physiology, Hosur Road, Adugodi, Bangalore 560030, Karnataka, India; and Corresponding author. Email: scroy67@gmail.com., Sakhare DT; Molecular Biology Laboratory, Indian Council of Agricultural Research-National Institute of Animal Nutrition and Physiology, Hosur Road, Adugodi, Bangalore 560030, Karnataka, India., Badami S; Molecular Biology Laboratory, Indian Council of Agricultural Research-National Institute of Animal Nutrition and Physiology, Hosur Road, Adugodi, Bangalore 560030, Karnataka, India., Divyashree BC; Molecular Biology Laboratory, Indian Council of Agricultural Research-National Institute of Animal Nutrition and Physiology, Hosur Road, Adugodi, Bangalore 560030, Karnataka, India., Gurupriya VS; Molecular Biology Laboratory, Indian Council of Agricultural Research-National Institute of Animal Nutrition and Physiology, Hosur Road, Adugodi, Bangalore 560030, Karnataka, India., Dhali A; Molecular Biology Laboratory, Indian Council of Agricultural Research-National Institute of Animal Nutrition and Physiology, Hosur Road, Adugodi, Bangalore 560030, Karnataka, India. |
| Abstrakt: |
The motility and fertility of mammalian spermatozoa are compromised when they are cryopreserved. Sperm mitochondrial proteins play a vital role in conferring motility. However, the effects of cryopreservation on mitochondria-specific proteins remain primarily unexplored in domestic animals, including buffaloes, so the present study aimed to evaluate this issue. Mitochondria were isolated from both non-cryopreserved and cryopreserved buffalo spermatozoa by sonication followed by sucrose density gradient ultracentrifugation. The purity of the mitochondrial preparation was assessed by cytochrome oxidase assay and electron microscopy. Mitochondria separated from cryopreserved buffalo spermatozoa were associated with significantly lower (P ≤ 0.05) cytochrome oxidase activity as compared with non-cryopreserved spermatozoa. The intensities of two low-molecular-mass mitochondrial proteins (30.1 kDa and 26.1 kDa) were significantly reduced as compared with the non-cryopreserved group. In addition, in cryopreserved buffalo sperm mitochondria, the intensities of three tyrosine phosphorylated proteins (126.6, 106.7 and 26 kDa) increased significantly compared with the non-cryopreserved group. Of these, tyrosine phosphorylation of the 26-kDa mitochondrial protein of cryopreserved sperm was very intense and unique because it could not be detected in the mitochondria of non-cryopreserved sperm. Thus, the study confirmed that both cytochrome oxidase activity and the proteins of buffalo sperm mitochondria undergo significant cryogenic changes in terms of quantity and quality after a cycle of freezing and thawing and this may be one of the important causes of reduced post-thaw motility and fertility of cryopreserved buffalo spermatozoa. |
