Review: genetic background of milk fatty acid synthesis in bovines.

Milk fat composition is an important trait for the dairy industry as it directly influences the nutritional and technological properties of milk and other dairy products. The synthesis of milk fat is a complex process regulated by a network of genes. Thus, understanding the genetic variation and molecular mechanisms regulating milk fat synthesis will help to improve the nutritional quality of dairy products. In this review, we provide an overview of milk fat synthesis in bovines along with the candidate genes involved in the pathway. We also discuss de novo synthesis of fatty acids (ACSS, ACACA, FASN), uptake of FAs (FATP, FAT, LPL), intracellular activation and channelling of FAs (ACSL, FABP), elongation (EVOLV6), desaturation (SCD, FADS), formation of triglycerides (GPAM, AGPAT, LIPIN, DGAT), and milk lipid secretion (BTN1A1, XDH, PLIN2). The genetic variability of individual fatty acids will help to develop selection strategies for obtaining a healthier milk fat profile in bovines. Thus, this review will offer a potential understanding of the molecular mechanisms that regulate milk fat synthesis in bovines.

Genetic analysis of milk minerals in dairy cattle: a review.

Mineral composition in milk can affect its nutritional as well as physio-chemical properties of milk and is considered an important trait in the evaluation of milk quality. The composition and concentration of milk minerals could be altered with natural source of variation including nutrition and genetics. The effect of diet on milk minerals is well studied. However, genetic effects on the milk minerals have recently gained the attention. This review provides an overview of the genetic variation of milk minerals, and the genomic regions associated with mineral concentration in the milk are also discussed. The difference of milk minerals between breeds and the genetic parameters including heritability estimates and correlation among minerals indicates that milk minerals are under strong genetic control. Recently, the genome-wide association study (GWAS) has explored several regions associated with milk minerals and thus provides a new genetic source for improving the milk quality through genomics-assisted breeding. Hence, a combination of the qualitative and molecular approaches can be exploited to improving the nutritional quality of cattle milk in terms of its mineral composition.

Molecular characterization, putative structure and function, and expression profile of OAS1 gene in the endometrium of goats (Capra hircus).

An interferon-inducible gene, 2'-5'-oligoadenylate synthetase-1 (OAS1), plays an essential role in uterine receptivity and conceptus development by controlling cell growth and differentiation in addition to anti-viral activities. As OAS1 gene has not yet been studied in caprine (cp), so present study was designed with the aim to amplify, sequence, characterize and in-silico analyze the coding sequence of the cpOAS1. Further, expression profile of cpOAS1 was performed by quantitative real-time PCR and western blot in the endometrium of pregnant and cyclic does. An 890 bp fragment of the cpOAS1 was amplified and sequenced. Nucleotide and deduced amino acid sequences revealed 99.6-72.3% identities with that of ruminants and non-ruminants. A constructed phylogenetic tree revealed that Ovis aries and Capra hircus differ from large ungulates. Various post-translational modifications (PTMs), 21 phosphorylation, two sumoylation, eight cysteines and 14 immunogenic sites were found in the cpOAS1. The domain, OAS1_C, is found in the cpOAS1 which carries anti-viral enzymatic activity, cell growth, and differentiation. Among the interacted proteins with cpOAS1, Mx1 and ISG17 well-known proteins are found that have anti-viral activity and play an important role during early pregnancy in ruminants. CpOAS1 protein (42/46 kDa and/or 69/71 kDa) was detected in the endometrium of pregnant and cyclic does. Both cpOAS1 mRNA and protein were expressed maximally (P<0.05) in the endometrium during pregnancy as compared to cyclic does. In conclusion, the cpOAS1 sequence is almost similar in structure and probably in function also to other species along with its higher expression during early pregnancy.

Kinetics of GDF9 expression in buffalo oocytes during in vitro maturation and their associated development ability.

The capacity of fully grown oocytes to regulate their own microenvironment by secreted paracrine factors contribute to their developmental competence. In spite of growing evidence about the vital role of Growth Differentiation Factor 9 (GDF9) in determination of oocyte developmental competence, there is insufficient information about time dependent behavior of its expression during in vitro maturation (IVM) to have definite understanding about at what time point during IVM it plays most crucial role. The study reports the kinetics of GDF9 expression under four different IVM supplement conditions in buffalo oocytes and their concomitant development rate up to blastocyst. Oocytes matured under an ideal media condition with all supplements and those cultured with only FSH resulted in significantly higher cumulus expansion, nuclear maturation, cleavage and blastocyst rates. GDF9 expression at both mRNA and protein levels at different time points of IVM revealed that magnitude of mRNA abundance at 8h of IVM was most important towards imparting development competence to buffalo oocytes. Appearance of GDF9 protein in maturing oocytes was found asynchronous with mRNA appearance in the time course of IVM suggesting possible posttranscriptional regulation of this gene under dynamic oocyte cumulus cell communication process. Abundance of mature GDF9 protein at 16 h was most consistently related with all oocyte development parameters.

Myxovirus resistance 1 (Mx1) gene: Molecular characterization of complete coding sequence and expression profile in the endometrium of goat (Capra hircus).

Myxovirus resistance 1 (Mx1) gene plays an important role in uterine receptivity and conceptus development by creating a strong defense mechanism in the uterine environment. However, the specific role of Mx1 gene is not yet documented in the goat. Therefore, in the present study, full-length coding sequence (CDS) of the Mx1 gene was amplified, sequenced and characterized through various Bioinformatic tools. Temporal expression profile of Mx1 mRNA and protein was also examined by quantitative real-time PCR (qPCR) and western blot, respectively, in the endometrium of cyclic stage (non-pregnant), pregnancy stage I (16-24 days of gestation) and pregnancy stage II (25-40 days of gestation) of caprine (cp). A fragment of the cpMx1 gene, 2144 bp in length, was amplified from complementary DNA (cDNA) with a 1965 bp open reading frame. Coding and deduced amino acid sequences of the cpMx1 were aligned with other species and it exhibited 98.8-81.5 % identities with different species. On phylogenetic analysis, sheep and goat were found belonging to the same clade but differing from large ruminants. The cpMx1 protein possess the conserved signature motif (LPRGTGIVTR) of dynamin superfamily and the tripartite guanosine-5'-triphosphate (GTP) binding motif (GDQSSGKS, DLPG, TKPD) at the N-terminal end, and the leucine zipper motifs at the C-terminal end. Both cpMx1 mRNA and protein were found to be expressed maximally (P < 0.05) in the pregnancy stage I as compared to cyclic stage. It was concluded that the cpMx1 gene shares major structural and probably functional similarities with other species.

Interferon stimulated gene 15 (ISG15): molecular characterization and expression profile in endometrium of buffalo (Bubalus bubalis).

Interferon stimulated gene 15 (ISG15), one of the several proteins induced by conceptus derived Type I and/or a Type II interferon (IFN), is implicated as an important factor in determining the uterine receptivity and conceptus development. However, presence as well as specific role of the ISG15 in buffalo (Bubalus bubalis) reproduction is yet to be elucidated. In the present study, both genomic and cDNA sequences of bubaline (bu) ISG15 were cloned and investigated for its expression in different tissues of female reproductive tract of buffalo. Sequence analysis revealed 100% identity among the genomic sequences (1014 bp) of buISG15 from three different breeds of buffalo (viz., Murrah: Acc. No. DQ118137, Mehsana: Acc. No. DQ118138, and Nagpuri: Acc. No. DQ118136) and cDNAs (Acc. Nos. HM543268-HM543270). As in cattle, the buISG15 was comprised of two exons of 57 bp and 520 bp encoding a peptide of 154 amino acids. Moreover, the buISG15 cDNA sequence exhibited 98.3% and 98.5% identity with that of taurine and indicine cattle, respectively. Subsequent reverse transcription PCR analysis revealed expression of the buISG15 in the uterine endometrium, corpus luteum (CL), corpus hemorrhagicum and oviduct. Quantitative Real Time PCR (RTqPCR) analysis also confirmed the constitutive expression of the buISG15 in the uterine endometrium during different stages (i.e. estrus, diestrus and proestrus) of estrous cycle and also during early (∼d 30-40) pregnancy. Western blot analysis of the endometrial extract from both estrous cyclic as well as pregnant buffalo demonstrated the presence of only conjugated ISG15 which was >40 kDa. ISG15 mRNA and immune-reactive proteins were localized in the stromal as well as glandular epithelial cells of the uterine endometrium of estrous cyclic as well as pregnant buffalo. However, there was no significant difference in amount of ISG15 mRNA across the different reproductive phases. To conclude, this study will be helpful for the further understanding of the roles of the ISG15 in pregnancy of buffalo cows.

Molecular characterization and expression profile of uterine serpin (SERPINA14) during different reproductive phases in water buffalo (Bubalus bubalis).

Uterine serpins (SERPINA14) play important roles during pregnancy in the farm animals. In this study, we have cloned and characterized cDNA sequence encoding the bubaline SERPINA14. We also studied its spatio-temporal expression in the uterine endometrium. The bubaline SERPINA14 has an open reading frame of 1299bp. Itshares ∼90% identity with the SERPINA14 of other ruminant livestock species. Phylogenetically, bubaline SERPINA14 has been placed in the same clade that contained other mammalian homologues with a maximum identity to bovine SERPINA14. Using an anti-ovine monoclonal antibody, Western blot analysis of the uterine fluid of buffalo during the early stage of pregnancy confirmed the presence of SERPINA14 of about 48,000Da. The results of quantitative real time PCR (RT-qPCR) as well as in situ hybridization demonstrated a stage and tissue specific expression of bubaline SERPINA14. The level of SERPINA14 mRNA was low during stage I (Days 3-5), which increased (P<0.05) during stage II (Days 6-15) and then subsequently declined during stage III (Days 16-21) of the estrus cycle. During early pregnancy (Days ∼30 of gestation) the level of SERPINA14 mRNA was as high as that during stage II of the estrus cycle. The SERPINA14 mRNA was localized in the glandular epithelium. The differential spatio-temporal expression of SERPINA14 in the uterine endometrium of buffalo suggests its plausible important roles in reproduction.