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We used 2D-PAGE to isolate a light-induced protein (AL-A) that is expressed abundantly in light-growth alfalfa sprouts. The seven amino acids of the N-terminal region of the protein were identified, and we searched for the protein in GenBank using the BLAST program. The results of the homology analysis showed that the amino acid sequence of the isolated protein is most similar to one from a pea plastocyanin. To identify the protein, we amplified and sequenced the DNA fragment encoding AL-A from genomic alfalfa DNA. We found that the AL-A gene was highly homologous (90%) to the sequences from the pea plastocyanin via multiple alignments, and the deduced protein precursor was predicted to be chloroplast-specific via the ChloroP computer program. The protein was named alfalfa-plastocyanin (AL-P). It was characterized as being a light-inducible protein, and RT-PCR analysis showed that AL-P mRNA transcription only occurred in the leaves of the alfalfa plant and the alfalfa seedlings growth in lighted conditions. PCR was also used to amplify the DNA fragment encoding the AL-P promoter (AL-Pp) from genomic alfalfa DNA. PlantCARE analysis of the promoter sequence indicated that both a typical TATA box and a CAAT box were located in the promoter sequence, and some of the cis-elements that are responsible for light responsiveness were also identified within this promoter region. The AL-P gene promoter fused to the β-glucuronidase (GUS) reporter gene has been examined for expression in transgenic alfalfa seedlings. Our findings have a potential application in plant genetic engineering; the AL-Pp may be used to drive the expression of heterologous genes in transgenic alfalfa plants.

The gene targeting combined somatic cell nuclear transfer is very useful in agriculture and medicine. Epigenetic modification of DNA by methylation is significant in regulating gene expression during mammalian development. During gene targeting, epigenetic status of donor cell nuclei may be changed in a series of processes, including homologous recombination, cell selection and cloning. We examined DNA methylation of six genes ( β-actin , VEGF , oct4 , TERT , H19 and Igf2 ) and a repetitive sequence art 2 in blg +/− cell line from β-lactoglobulin (BLG) gene targeted fetus and the cells used for BLG gene targeting serve as control. The results demonstrated that the widespread changes of DNA methylation were found in blg +/− cell line. But the degree of variation was different. DNA methylation of VEGF in blg +/− was noticeably decreased. These observations suggest that DNA methylation variations may impact gene expression and finally induce abnormalities and lethality in later developmental stages.

Lmbr1 is regarded as a key gene that controls the digital model formation in early developmental stages of the chicken. However, there are few reports of lmbr1 expression levels and tendencies in 4-toe and 5-toe chicken species. Therefore, the objective of this study was to compare the lmbr1 expression in White Leghorn (4-toe) and Chinese Silky (5-toe). Firstly, total RNA was extracted from 14 different embryonic development stages (HH3 to HH31) in White Leghorn and Chinese Silky. Secondly, dramatic gene expression changes of lmbr1 were monitored by RT-PCR, which indicated a general up-down-up tendency with subtle differences between these two species. Moreover, Q-PCR reactions were performed to quantitate the expression level of lmbr1 in the 14 selected developmental stages. These data demonstrated a first lmbr1 expression peak of 18.68 and 15.32, a lmbr1 expression trough of 6.61 and 1.80, and a second lmbr1 expression peak of 22.33 and 12.48 in White Leghorn and Chinese Silky, respectively. Finally, embryonic in situ hybridization analysis identified that lmbr1 expressed in the ectoderm in HH21, HH23 and HH24 developmental stages in both species.

Summary Transmissible spongiform encephalopathy (TSE) is a neurodegenerative disorder in humans and animals. Polymorphisms and mutations in the prion protein (PRNP) gene have been associated with the incidence of natural and experimental TSE and the incubation period length. In this study, we determined PRNP polymorphisms in Chinese ovine, caprine and bovine breeds using 400 samples from 13 ovine and caprine breeds and 250 samples from nine bovine breeds. In the ovine and caprine PRNP gene, we found five previously unreported amino acid polymorphisms and two silent nucleotide alterations. In bovine PRNP, we found eight previously unreported amino acid polymorphisms and six silent nucleotide alterations.

A chicken bacterial artificial chromosome (BAC) library consisting of 138,240 clones was constructed in vector pBeloBAC11 with genomic DNA isolated from female white‐silk chicken. An average insert size of 118 kb was estimated from 452 randomly isolated clones, which indicate the library to be approximate 13.34‐fold genome coverage. For the demonstration of the probability to pick out any unique genes or DNA markers from the library, 8 single‐copy genes were screened out and the positive clones were yielded between 2 and 15 with an average of 11.125, in agreement with the estimated high genomic coverage of this library. Positive superpools were obtained for 40 microsatellite markers selected from different regions of chicken genome. The number of positive superpools for each marker varies from 1 to 15 with an average of 9.475.