Polymorphism Identification, RH Mapping and Association of ${\alpha}$-Lactalbumin Gene with Milk Performance Traits in Chinese Holstein

Zhang, Jian,Sun, Dongxiao,Womack, J.E.,Zhang, Yi,Wang, Yachun,Zhang, Yuan Asian Australasian Association of Animal Productio 2007 Animal Bioscience Vol.20 No.9

Lactose synthase catalyses the formation of lactose which is the major osmole of bovine milk and regulates the milk volume. Alpha-lactalbumin (${\alpha}$-LA) is involved in the synthesis of lactose synthase in the mammary gland. Therefore ${\alpha}$-LA is regarded as a plausible candidate gene for the milk yield trait. To determine whether ${\alpha}$-LA is associated with milk performance traits, 1,028 Chinese Holstein cows were used to detect polymorphisms in the ${\alpha}$-LA by means of single-strand conformation polymorphism (SSCP). Two nucleotide transitions were identified in the 5'flanking region and intron 3 of ${\alpha}$-LA. Associations of such polymorphisms with five milk performance traits were analyzed using a general linear model procedure. No significant associations were observed between these polymorphisms and the five milk performance traits (p>0.05). RH mapping placed ${\alpha}$-LA on BTA5q21, linked most closely to markers U63110, CC537786 and L10347 (LOD>8.3), which is far distant from the region of the quantitative trait locus (QTL) on bovine chromosome 5 for variation in the milk yield trait. In summary, based on our findings, we eliminated these SNPs from having an effect on milk performance traits.

Performance Analysis of OT-MRC Over I.I.D. Nakagami and Non-I.I.D. Rayleigh Fading Channels

Nam, Haewoon,Ko, Young-Chai,Womack, Baxter F. IEEE 2006 IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY Vol.55 No.6

<P>This paper presents the performance analysis of a conditional diversity combining scheme, which is called output-threshold maximum ratio combining (OT-MRC), over the independent identically distributed Nakagami-m with integer m and independent but not necessarily identically distributed Rayleigh fading channels. Based on the closed-form expressions for the statistics, the authors analyze the performance of the OT-MRC systems and compare it with that of the conventional MRC systems. They exploit the tradeoff between complexity and performance in this scheme over the Nakagami fading channels and see the effect of unbalance of the fading gains over multiple diversity branches on the performance of OT-MRC. They show, from some numerical examples, that the OT-MRC scheme, when compared with the MRC scheme, can reduce the complexity significantly without losing the required performance</P>

Power Loading Using Order Mapping in OFDM Systems With Limited Feedback

Choi, E.H.,Wan Choi,Andrews, J.G.,Womack, B.F. IEEE 2008 IEEE signal processing letters Vol.15 No.1

<P>This letter proposes an approximate waterfill power loading scheme using limited feedback in orthogonal frequency division multiplexing (OFDM) systems. The proposed technique achieves nearly the capacity of optimal waterfill power loading, while significantly reducing feedback by using order information for the subcarrier channel gains. Furthermore, the proposed power loading technique can circumvent the practical shortcomings of previous limited feedback power loading techniques by simply exploiting order mapping and interpolation. The advantages are particularly visible at low SNR or for many subcarriers, both of which will be very common in emerging wireless broadband OFDM standards.</P>

Gene expression and DNA methylation status of chicken primordial germ cells.

Jang, Hyun-Jun,Seo, Hee Won,Lee, Bo Ram,Yoo, Min,Womack, James E,Han, Jae Yong Humana Press 2013 Molecular biotechnology Vol.54 No.2

<P>DNA methylation reprogramming of primordial germ cells (PGCs) in mammals establishes monoallelic expression of imprinting genes, maintains retrotransposons in an inactive state, inactivates one of the two X chromosomes, and suppresses gene expression. However, the roles of DNA methylation in chickens PGCs are unknown. In this study, we found a 1.5-fold or greater difference in the expression of 261 transcripts when comparing PGCs and chicken embryonic fibroblasts (CEFs) using an Affymetrix GeneChip Chicken Genome Array. In addition, we analyzed the methylation patterns of the regions ~5-kb upstream of 261 sorted genes, 51 of which were imprinting homologous loci and 49 of which were X-linked homologous loci in chicken using the MeDIP Array by Roche NimbleGen. Seven hypomethylated and five hypermethylated regions within the 5-kb upstream regions of 261 genes were found in PGCs when compared with CEFs. These differentially methylated regions were restrictively matched to differentially expressed genes in PGCs. We also detected 203 differentially methylated regions within imprinting and X-linked homologous regions between male PGCs and female PGCs. These differentially methylated regions may be directly or indirectly associated with gene expression during early embryonic development, and the epigenetic difference could be evolutionally conserved between mammals and birds.</P>

Biomechanical and Physiological Effects of Plyometric Training on Adolescent Cross-Country Runners

( Mark C. Lathrop ),( Eugene W. Brown ),( Chris J. Womack ),( V. Diarme Ulibarri ),( Chad Paton ),( Pete Osmond ) 한국스포츠정책과학원(구 한국스포츠개발원) 2001 International Journal of Applied Sports Sciences Vol.13 No.2

The purpose of this study was to compare the effectiveness of a traditional high school (14 to 18 years of age) cross-country training regimen typically used in the United States with a training program that includes plyometrics. The results of this study may be generalizable to similar training programs used by cross-country coaches of young athletes. Eighteen male and female cross-country runners were matched according to their previous running experience and randomly assigned to two groups. Participants followed a traditional cross-country training program for six weeks, except that two to three times a week the plyometrics group replaced some of their easy run training with 15-20 minutes of plyometric training. The participants were tested before and after the six-week training period. A treadmill test was used to determine running economy and VO2max. The participants were also evaluated by having them run across a force plate in order to determine support time, braking time, and braking change in velocity. Participants were also timed on a 3200-meter run in order to determine endurance performance. The dependent variables were each analyzed in a Group (PLYO vs. RUN) x Time (Pretest vs. Posttest) two-way mixed ANOVA. Participants in both groups significantly improved their running economy, (F (1, 14) = 44.47, P < .0001) and 3200-meter time, (F (1,14) = 8.13, p = .013), while braking change in velocity decreased significantly (F (1, 14) = 6.19, p = .026) from pretest to posttest. There was a trend of a Group x Time interaction effect for braking change in velocity (F(1, 14) = 3.31, p = .09) although it was not significant. The plyometric group decreased their braking change in velocity over the training period (although it was not significant), while there was no change in the running group. There were no significant differences between groups on any of the other dependent variables. These results suggest that replacing some run training with plyometrics for a short period of time in young cross-country runners does not enhance running performance or performance-related variables more than run-only training. However, the observed decrease in braking change in velocity may suggest biomechanical adaptations occur that could possibly impact performance if a long-term intervention is initiated.

Chicken NK-lysin is an α-helical cationic peptide that exerts its antibacterial activity through damage of bacterial cell membranes

Lee, M.O.,Jang, H.-J.,Han, J.Y.,Womack, J.E. POULTRY SCIENCE ASSOCIATION 2014 Poultry science Vol.93 No.4

Biallelic expression of the L-arginine:glycine amidinotransferase gene with different methylation status between male and female primordial germ cells in chickens.

Jang, H J,Lee, M O,Kim, S,Kim, T H,Kim, S K,Song, G,Womack, J E,Han, J Y Poultry Science Association, etc 2013 Poultry science Vol.92 No.3

<P>The basic functions of DNA methylation include in gene silencing by methylation of specific gene promoters, defense of the host genome from retrovirus, and transcriptional suppression of transgenes. In addition, genomic imprinting, by which certain genes are expressed in a parent-of-origin-specific manner, has been observed in a wide range of plants and animals and has been associated with differential methylation. However, imprinting phenomena of DNA methylation effects have not been revealed in chickens. To analyze whether genomic imprinting occurs in chickens, methyl-DNA immunoprecipitation array analysis was applied across the entire genome of germ cells in early chick embryos. A differentially methylated region (DMR) was detected in the eighth intron of the l-arginine:glycine amidinotransferase (GATM) gene. When the DMR in GATM was analyzed by bisulfite sequencing, the methylation in male primordial germ cells (PGC) of 6-d-old embryos was higher than that in female PGC (57.5 vs. 35.0%). At 8 d, the DMR methylation of GATM in male PGC was 3.7-fold higher than that in female PGC (65.0 vs. 17.5%). Subsequently, to investigate mono- or biallelic expression of the GATM gene during embryo development, we found 2 indel sequences (GTTTAATGC and CAAAAA) within the GATM 3'-untranslated region in Korean Oge (KO) and White Leghorn (WL) chickens. When individual WL and KO chickens were genotyped for indel sequences, 3 allele combinations (homozygous insertion, homozygous deletion, and heterozygotes) were detected in both breeds using a gel shift assay and high-resolution melt assay. The deletion allele was predominant in KO, whereas the insertion allele was predominant in WL. Heterozygous animals were evenly distributed in both breeds (P < 0.01). Despite the different methylation status between male and female PGC, the GATM gene conclusively displayed biallelic expression in PGC as well as somatic embryonic, extraembryonic, and adult chicken tissues.</P>

Cloning and Characterization of Bovine Titin-cap (TCAP) Gene

Yu, S.L.,Chung, H.J.,Jung, K.C.,Sang, B.C.,Yoon, D.H.,Lee, S.H.,Kata, S.R.,Womack, J.E.,Lee, J.H. Asian Australasian Association of Animal Productio 2004 Animal Bioscience Vol.17 No.10

Titin-cap (TCAP), one of the abundant transcripts in skeletal muscles, was nvestigated in this study in cattle because of its role in regulating the proliferation and differentiation of myoblasts by interacting with the myostatin gene. From the 5, and 3, RACE experiments, full-length TCAP coding sequence was identified, comprising 166 amino acids. The amino acid comparison showed high sequence similarities with previously identified human (95.8%) and mouse (95.2%) TCAP genes. The TCAP expression, addressed by northern blot, is limited in muscle tissues as indicated by Valle et al. (1997). The radiation hybrid analysis localized the gene on BTA19, where the comparative human and porcine counterparts are on HSA17 and SSC12. A few muscle-related genetic disorders were mapped on HSA17 and some growth-related QTLs were identified on SSC12. The bovine TCAP gene found in this study opens up new possibilities for the investigation of muscle-related genetic diseases as well as meat yield traits in cattle.