Cloning and transcriptional activity of a novel ovarian-specific promoter from rat retrovirus-like elements

Transcriptional activity of an ovarian-specific promoter from rat in dairy goat granulosa cells

Ovarian-specific promoter 1 (OSP-1) is a retrovirus-like element isolated from the complementary DNA library of rat that has been thought to be specifically expressed in ovary. To exploit this promoter in dairy goat ovary granulosa cells (GCs), OSP-1 from rat was used to construct the reporter vector pOSP-1-EGFP, in which egfp coding for enhanced green fluorescent protein (EGFP) was used as a reporter to examine the activity of OSP-1 in GCs. EGFP was successfully expressed in dairy goat GCs transfected with pOSP-1-EGFP. Reverse transcriptase-polymerase chain reaction analysis confirmed the tissue-specific transcription of EGFP messenger RNA in dairy goat GCs transfected with pOSP-1-EGFP. We concluded that OSP-1 promoter from rat can specifically drive foreign gene expression in dairy goat GCs. Thus, we obtained a tissue-specific regulation element and provided a potential tool for the research of regulation and development of the ovary in dairy goats.

Expression of an alfalfa (Medicago sativa L.) ethylene response factor gene MsERF8 in tobacco plants enhances resistance to salinity

Ethylene response factors (ERF) play crucial roles in plant development and response to stresses. Here, a novel cDNA fragment (MsERF8) encoding an ERF protein with an AP2 domain was isolated and characterized from alfalfa. The MsERF8 cDNA has an open reading frame of 603 bp and encodes a nuclear protein of 201 amino acids. Q-RT-PCR analysis revealed that MsERF8 was strongly enriched in roots and leaves compared with stems, flower buds and flowers of mature alfalfa plants. Bioinformatic analysis of the MsERF8 promoter indicated a number of elements associated with stress-related responses, and MsERF8 transcripts in alfalfa seedlings were induced by NaCl, PEG6000, Al(2)(SO(4))(3) and five different hormones. Expression of MsERF8 in transgenic tobacco plants resulted in higher tolerance to salinity than with non-transgenic plants. This data shows that MsERF8 is a gene which prevents or alleviates salinity damage and has strong potential to impart salt tolerance to other crop plants.

Molecular cloning and characterization of an achene-seed-specific promoter from motherwort (Leonurus japonicus Houtt)

LJAMP1 is a small antimicrobial protein purified previously from the seeds of motherwort, and it is expressed preferentially in seeds. A 794-bp upstream sequence of the ATG start codon was isolated using a genome walking method and cloned into the upstream of the β-glucuronidase (GUS) reporter gene to determine the GUS tissue-specific expression pattern. The transgenic tobacco showed that pLJAMP1 promoter derived GUS reporter gene special expression in pollen, achene and seed. The analysis of cis-acting elements also revealed pLJAMP1 promoter contained pollen and seed related transcriptional control elements.

Protection of CHO cells by transfer of survivin driven by ovarian-specific promoter OSP-2

Chemotherapy is the major therapy for cancer in clinic. However, chemotherapeutic agents can harm the other tissues/organs besides cancer. Thus, there are great interests in protecting the innocents by the transfer of protective genes. There are two problems to be solved, one is the selection of protective genes and the other is the orientation of the exotic genes. Recent researches demonstrated that the principal mechanism of chemotherapeutics was through apoptosis. Hereby, introduction of anti-apoptosis genes might interrupt the processes of apoptosis to avoid side effect from chemotherapeutics. On the other hand, tissue-specific promoters, which control gene expression in a tissue-specific manner, might be an alternative tool to guarantee the location of target genes. In this research, we applied gene therapy to chemoprotection using anti-apoptosis gene survivin and ovarian-specific promoter OSP-2. The results showed that OSP-2 could specifically drive the expression of survivin in ovarian cells and survivin could protect cells via inhibiting apoptosis. This might put a light on the future of chemoprotective gene therapy.