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PubMed2006

Prevalence of erythrocyte glucose-6-phosphate dehydrogenase (G6PD) deficiency in the population of western Turkey.

BACKGROUND: Newborn G6PD deficiency screening has been recognized as an essential component of public health care in most developed and some Mediterranean countries. However, such screening is yet to be widely embraced in Turkey. The aim of the present study was to determine the normal values of G6PD and deficiency prevalence of this enzyme in different age groups of people living in the western region of Turkey and accordingly inform and educate about favism to those asymptomatic carriers who usually are not aware of their G6PD deficient status. METHODS: A total of 1421 clinically healthy individuals without evidence of leukocytosis or thrombocytosis were included in the study. Activity of G6PD was quantitatively measured. RESULTS: Normal mean values of G6PD in healthy males were 8.94 +/- 8.65 IU/g Hb (or 231.73 +/- 43.16 IU/10(12) RBC), in females were 9.16 +/- 3.78 IU/g Hb (or 219.9 +/- 43.1 IU/10(12) RBC). The frequencies of severe and mild G6PD deficiencies were 0.44% and 6.07% in females, respectively, whereas in males it was 7.24%. Overall frequency of the G6PD-deficient phenotype was detected as 6.9%. CONCLUSIONS: There is no significant statistical difference of G6PD activity between males and females, although frequency of the G6PD-deficient phenotype is relatively high in western Turkey. The results emphasize a need for screening for G6PD deficiency before prescribing anti-malarial therapy with drugs like primaquine to patients in this region of Turkey known for its prevalence of malaria.

Erythrocytes↗
PubMed2006

Treatment of turkey processing wastewater with sand filtration.

This research investigated the feasibility of coarse/fine sand filtration for removing organic materials from turkey processing wastewater. Sand filtration was tested with three organic and hydraulic loadings. Six two-layer sand bioreactors were in three groups, each with 5 cm layer of pea gravel at the bottom to support layers of fine sand (46 cm) and coarse sand (15 cm) to a height of 66 cm. The bioreactors were inoculated with a mixture of 20% (vol/vol) of wastewater lagoon sludge, 40% (vol/vol) of turkey processing wastewater, and 40% (vol/vol) of BOD(5) dilution water before starting the column operation with turkey processing wastewater. The wastewater contained 1270+/-730 mg COD/L and was applied to each sand bioreactor at hydraulic loading rates of 94% during 80 days of column operation at low and medium hydraulic loading rates (132 L/m(2)/day). The removal at the highest hydraulic loading rate (264 L/m(2)/day) declined after the appearance of a black zone in the top layer of fine sand on day 30 for one reactor and day 50 for the other. The sand filtration in this study represents a feasible treatment for turkey processing wastewater and its efficiency and the life span of the process are associated with the extent of hydraulic loading of the sand bioreactors.

Animals↗
PubMed2005

Expression of insulin-like growth factor system genes in liver and brain tissue during embryonic and post-hatch development of the turkey.

A molecular cloning strategy employing primer-directed reverse transcription polymerase chain reaction (RT-PCR) was devised to sequence 1300 bp of a turkey liver-derived cDNA corresponding to the complete coding region and the 5'- and 3'-untranslated regions of the insulin-like growth factor (IGF)-II mRNA transcript (GenBank accession no. ). The turkey IGF-II gene codes for a 187 amino acid precursor protein that includes a signal peptide, the mature IGF-II hormone, and a C-terminal extension peptide comprised of 24, 67 and 96 amino acids, respectively. Turkey IGF-II showed greater than 95% sequence identity at both the nucleotide and amino acid level with chicken IGF-II. Expression of IGF-I, IGF-II, IGF type-I receptor (IGF-IR), and IGF binding protein (IGFBP)-2 and -5 genes was quantified relative to an internal 18S rRNA standard by RT-PCR in liver and whole brain tissue on days 14, 16, 18, 20, 22, 24 and 26 of embryonic development, as well as at hatch (H, day 28) and at 3 weeks post-hatching (PH). Expression of liver IGF-I was low throughout embryonic development, but increased more than 8-fold by 3 weeks PH. In contrast, IGF-I was expressed in brain tissue at much higher levels than liver throughout development and this level of expression in brain increased gradually, reaching its highest point at 3 weeks PH. IGF-II was expressed at comparable levels in brain and liver tissue during embryonic development, except for transient increases in liver just prior to hatching (days 24 and 26) and at 3 weeks PH. Expression of IGF-IR declined in brain throughout development reaching its lowest level at 3 weeks PH. In liver, IGF-IR expression was lower than that of brain throughout development. An inverse relationship was observed for the expression of IGF-I and IGF-IR genes in brain, but not in liver, through 3 weeks PH. Expression of the IGFBP-2 gene increased in liver around the time of hatch (days 26-28) and declined by 3 weeks PH, whereas the level of expression of IGFBP-5, which was higher than IGFBP-2, remained fairly constant in both brain and liver throughout the developmental period studied. Our data indicates differential expression of selected genes that comprise the IGF system in the turkey during embryonic and PH growth and development.

Amino Acid Sequence↗
PubMed2006

Eradication of Helicobacter pylori with triple therapy: an epidemiologic analysis of trends in Turkey over 10 years.

BACKGROUND: There is increasing concern about the efficacy of current regimens for the eradication of Helicobacter pylori. OBJECTIVES: This study examined rates of H. pylori eradication with a commonly used triple-therapy regimen consisting of a proton pump inhibitor (PPI), clarithromycin, and amoxicillin in trials performed in Turkey from 1996 to 2005. It also investigated the relationship between eradication rates and the duration of treatment (7, 10, or 14 days), choice of PPI, and indication for treatment (dyspepsia or peptic ulcer). METHODS: This was a retrospective epidemiologic analysis. Articles concerning H. pylori eradication in Turkey that were published in peer-reviewed national and international journals were identified through searches of MEDLINE using the terms Helicobacter, eradication, and Turkey, and of the Turkish Medical Index using the terms Helicobacter and eradication. Abstracts from the Turkish Gastroenterology Congress from 1996 through 2005 were searched manually. Open-label trials, controlled trials, treatment arms, and case series that included a triple-therapy regimen consisting of standard doses of any PPI (omeprazole 20 mg BID, lansoprazole 30 mg BID, pantoprazole 40 mg BID, or esomeprazole 40 mg BID) with clarithromycin 500 mg BID and amoxicillin 1 g BID for 7 to 14 days were selected for analysis. Trials including patients who had undergone a previous attempt at eradication of H. pylori were excluded. RESULTS: Of 138 trials or treatment arms identified, 94 met the criteria for inclusion (3637 subjects). The pooled eradication rate was 68.8% (95% CI, 67.3-70.3). A marked decrease in eradication was noted after 2000. Pooled eradication rates each year from 1996 through 2005 were 79.4%, 83.7%, 81.8%, 81.8%, 75.1%, 61.3%, 65.6%, 65.1%, 55.3%, and 61.1%, respectively. Eradication rates were not affected by the duration of treatment, choice of PPI, or indication for treatment. CONCLUSIONS: Rates of H. pylori eradication with the triple-therapy regimen decreased in Turkey over the 10-year period studied. In an era of increasing clarithromycin use, the effectiveness of this regimen for H. pylori eradication appears to require reassessment.

Amoxicillin↗
PubMed2004

Identification of two alphaRYR alleles and characterization of alphaRYR transcript variants in turkey skeletal muscle.

We hypothesized that a mutation in the turkey skeletal muscle ryanodine receptor alpha isoform (alphaRYR) underlies turkey meat quality problems which are strikingly similar to pale, soft, exudative (PSE) pork. RT-PCR analysis of turkey alphaRYR mRNA covering amino acids 376 to 615 (numbered according to the human sequence) revealed at least three transcript variants. One transcript was homologous to the mammalian skeletal muscle RYR1 sequence in this region. The second transcript variant (AS-81) was characterized by the absence of 81 bases located at the beginning of exon 13, while the third transcript variant (AS-193) carried a deletion of 193 bases, corresponding to the entire exon 13. Two alphaRYR genomic DNA alleles (alphaRYR-I and alphaRYR-II) carrying the region of deletions in the turkey cDNA sequences were identified. Nucleotide sequence analysis demonstrated that the two alleles are identical in exon sequences but different in intron sequences. Comparison of genomic and cDNA sequences indicated that both AS-81 and AS-193 transcript variants probably arose via alternative splicing. Consistent with this mechanism, the last eight nucleotides of the 81 bases form a consensus sequence for a splice acceptor site. Both alleles could give rise to the AS-81 and AS-193 transcript variants via alternative splicing. Birds homozygous for alphaRYR-II tended to have superior meat quality indicators including significantly higher muscle pH at 15-min post mortem and lower muscle exudate at 24-h post mortem, compared to birds homozygous for alphaRYR-I.

Alleles↗
PubMed2006

Genetic subtypes of human immunodeficiency virus type 1 (HIV-1) in Istanbul, Turkey.

BACKGROUND: Epidemiological surveillance of HIV-1 subtypes is an important and ongoing element of preparation for global antiviral interventions. OBJECTIVE: To assess the molecular epidemiology of HIV-1 in Istanbul, Turkey. STUDY DESIGN: 27 HIV/AIDS patients were investigated. Data on age, sex, country of birth, and HIV acquisition route were collected. Following amplification with PCR the sequences of the gp41 region of the env gene were determined using a 310 DNA sequencer (ABI prism, Foster City, USA) and phylogenetically analyzed. RESULTS: Among the 27 patients (26 adults and 1 infant), 22 were male, born in Turkey, and 20 infected through heterosexual contact. Two patients acquired the virus through blood and/or blood transfusion and one infant by vertical transmission. The distribution of the subtypes was as follows: four were subtype A, 19 subtype B, one subtype C, one subtype D, and two subtype F1. According to our results, although the B subtype is still predominant, non-B subtypes are also present, even though the number of registered HIV/AIDS patients is low. CONCLUSION: These are the first subtyped HIV-1 strains in Turkey where a low level of HIV prevalence has been observed since the first reported case in 1985. These findings and Turkey's specific geographic localization indicate the need for a nationwide surveillance to detect all subtypes including the new recombinant ones.

Adult↗
PubMed2006

Firearm-related deaths in two industrial cities of Turkey and their province.

We aimed to describe the characteristics of forensic autopsies of firearm-related deaths in two industrial cities of Turkey, in order to provide further data for the characterisation of firearm-related fatalities in Turkey, having the remarkable scarcity of such information from Turkey in mind. In the period from January 1999 until the end of 2003, 3463 autopsy records of the Morgue Departments of the Bursa and Kocaeli branch of the Turkish Council of Forensic Medicine were reviewed. Of the autopsies, 14.3% were firearm-related deaths. Of the cases, 17.8% were females and 82.2% were males. The median age was 34 for males and 25 for females. 51.3% were in the age group 21-40. The most frequent manner of death was homicide (62.2%). Both in suicides and in homicides, handgun weapons were the preferred weapons. 70.9% of the victims had a single entrance wound site and most common site was head (39.2%). In homicides 73.4% of the entrance wounds were caused by distant range shots. Death occurred in hospital and during the transfer to the hospital in 14.5% and 7.4% of the cases, respectively. The most common scene was outdoors in homicides (48.1%) and house in suicides (60.5%). Alcohol was found in 6.3% of the cases. It is obvious that private gun ownership should be strictly limited and the illegal availability should be prevented in order to decrease firearm-related deaths in Turkey.

Adolescent↗
PubMed2006

Effect of proteins from beef, pork, and turkey meat on plasma and liver lipids of rats compared with casein and soy protein.

OBJECTIVE: We assessed the effect of dietary proteins isolated from beef, pork, and turkey meat on concentrations of cholesterol and triacylglycerols in plasma, lipoproteins, and liver and the composition of the microsomal membrane (fatty acids, phosphatidylcholine/phosphatidylethanolamine ratio) compared with that of casein and soy protein in rats. METHODS: Five groups of 12 rats each were fed semisynthetic diets for 20 d that contained 200 g/kg of proteins isolated from beef, pork, or turkey meat or, as controls, casein or soy protein. RESULTS: Rats fed beef, pork, or turkey proteins did not differ in cholesterol concentrations of plasma, lipoproteins, and liver and in composition of microsomal membrane from rats fed the casein diet. All groups fed a protein from an animal source had higher very low-density lipoprotein (VLDL) and liver cholesterol concentrations than did rats fed soy protein. However, rats fed pork protein had lower concentrations of triacylglycerols in liver, plasma, and VLDL and lower mRNA concentrations of sterol regulatory element binding protein-1 and glucose-6-phosphate dehydrogenase than did rats fed casein. However, concentrations of plasma and VLDL triacylglycerols in rats fed pork protein were not as low as those observed in rats fed soy protein. CONCLUSION: Proteins isolated from beef, pork, or turkey meat do not differ from casein in their effects on cholesterol metabolism. Pork protein decreases plasma triacylglycerol concentrations compared with casein but not compared with soy protein. The triacylglycerol-lowering effect of pork protein compared with casein is suggested to be caused by decreased hepatic fatty acid synthesis.

Animals↗
PubMed2006

Broad dissemination of Histomonas meleagridis determined by the detection of nucleic acid in different organs after experimental infection of turkeys and specified pathogen-free chickens using a mono-eukaryotic culture of the parasite.

Histomonas meleagridis, a flagellated protozoan parasite, is the causative agent of histomonosis (syn. histomoniasis, blackhead) in turkeys and chickens. The organs primarily affected by the parasite are the caeca and the liver. Until now, only few reports exist in which the parasite has been diagnosed in tissues other than those mentioned above. Hence, the aim of this study was to perform a systematic investigation of various organs of turkeys and specified pathogen-free chickens following an experimental infection with a mono-eukaryotic culture of Histomonas meleagridis in order to determine the dissemination of the flagellate in infected birds. Molecular methods like PCR and in situ hybridization were used for this purpose. For the first time, the DNA of the parasite could be detected in 13 different organs of infected turkeys by PCR including the proventriculus, duodenum, jejunum, caeca, pancreas, bursa of Fabricius, liver, kidney, spleen, heart, lung, thymus and the brain. Most of these findings were further confirmed by in situ hybridization. In contrast to the turkeys that all died shortly after the infection, all of the chickens survived without displaying any clinical symptoms. Even at necropsy, only mild pathological changes were observed in the caeca. Nevertheless, the parasite could also be detected in various organs of these birds, namely the caeca, bursa of Fabricius, kidney, heart and the brain.

Animals↗
PubMed2005

Invoices and farmer interviews for vaccine-exposure measurement in turkey-broiler production.

Exposure measurement in pharmaco-epidemiological studies can be based on various sources that do not always concur. However, reliability is an important criterion when selecting the method used to assess exposure and interpreting the results obtained. An analysis based on invoices might be more informative and more accurate to assess vaccines exposure (yes/no) in turkey broiler production than a questionnaire administered to farmers, which is nevertheless more feasible and less time-consuming. We compared the two methods to assess vaccination exposure in 239 turkey broiler flocks reared in 129 farms in 2000-2001. The agreement (crude agreement and kappa) was calculated, and association between discrepancy and farm and flock characteristics was investigated. Marek's-disease vaccine, Newcastle-disease vaccine, turkey haemorrhagic-enteritis vaccine and turkey-rhinotracheitis vaccine exposures were reported on the questionnaire for 2.1, 27.6, 93.0, and 98.3% of flocks, respectively, and for 2.1, 29.3, 89.4, and 86.6%, of invoices for the flocks studied, respectively. A discrepancy was observed in 24.9% of flocks. A discrepancy was observed more frequently in specialised farms without any other animal production (OR = 3.6; CI = 1.5, 8.9) and when the farmer did not know whether vaccination had been performed in the hatchery (OR = 7.1; CI = 2.6, 19.7).

Animals↗
PubMed2004

The determinants of withdrawal use in Turkey: a husband's imposition or a woman's choice?

This paper seeks to understand why Turkey has one of the highest rates of withdrawal (coitus interruptus) use in the world. Despite a pronounced fertility decline, a marked increase in contraceptive prevalence, and expansion of family planning activities, in 1998 one in four Turkish couples relied on withdrawal, and this fraction has remained stable since 1983. In contrast to previous research that has focused on women's reports, here we use the husbands' module of the 1998 Turkish Demographic and Health Survey to examine user characteristics and attitudes, as well as the determinants of withdrawal use among a representative sample of 1950 currently married men in Turkey. Multivariate methods are employed to estimate these effects and the likelihood of using withdrawal rather than other methods. Among other findings, less egalitarian-minded husbands were more likely to select withdrawal over other contraceptive methods, but measures of male authority had only partial predictive power after controlling for other variables. Although withdrawal use typically reflects husbands' preferences, it is widely practiced as it satisfies user requirements and simplifies women's lives. The results of this study are discussed in a broader historical and cultural context and used to provide insight into how Turkey's family planning and reproductive health programs might be improved. In contrast to neighboring countries, there is little sign of withdrawal being displaced in Turkey anytime soon by modern methods.

Adult↗
PubMed2005

History of neurosurgery and neurosurgical applications in Turkey.

Although there is evidence of applications of cranial surgery in ancient times, it is commonly accepted that modern surgery started in the late 19th century. The advancements in anesthesiology and aseptic techniques were the main factors contributing to this process. Surgery of the nervous system, however, has a relatively shorter history than surgery of other systems. The process of surgical development in Turkey did not differ from most Western countries. Modern surgery started in 1890 in Turkey. In the beginning, neurosurgical applications were performed by general surgeons. Most of these applications included procedures for craniocerebral traumas and infections and procedures for pain relief. The first neurosurgeon, Dr. Tuner, started working in 1923, operating in some spinal cord and brain tumor and trigeminal neuralgia cases. Other neurosurgeons, Dr. Dilek, Dr. Baydur, and Dr. Kankat, were trained in France and started to work in the mid 1930s. The first neurosurgery department was established in Istanbul in 1923, and the first neurosurgery training program started in the late 1940s. Today, there are more than 50 neurosurgery training centers and more than 500 neurosurgeons in Turkey. There is an increasing number of publications by Turkish neurosurgeons, contributing to the total body of literature in neurosurgery. The current state of neurosurgery in Turkey is parallel to that of the advanced Western countries.

History, 15th Century↗
PubMed2005

Gelatinases and serine proteinase inhibitors of seminal plasma and the reproductive tract of turkey (Meleagris gallopavo).

This study examined proteolytic enzymes and serine proteinase inhibitors in turkey seminal plasma with relation to their distribution within the reproductive tract and to yellow semen syndrome (YSS). Proteases of blood plasma, extracts from the reproductive tract, and seminal plasma were analyzed by gelatin zymography. We found a clear regional distribution of proteolytic enzymes in the turkey reproductive tract. Each part was characterized by a unique profile of serine proteolytic enzymes of molecular weights ranging from 29 to 88 kDa. The ductus deferens was found to be a site of very intense proteolytic activity. Two metalloproteases of 58 and 66 kDa were detected in all parts of the reproductive tract and seminal plasma. Using electrophoretic methods for detection of anti-trypsin activity, we found three serine proteinase inhibitors in turkey seminal plasma. Two inhibitors were found in the testis and epididymis and a third in the ductus deferens and seminal plasma. Blood plasma was characterized by the presence of two metalloproteinases and one serine proteinase inhibitor (of low migration rate) that were also detected in the reproductive tract. Amidase and anti-trypsin activities (expressed per gram of protein) differed for yellow and white seminal plasma. We concluded that turkey seminal plasma contains metalloproteases, serine proteinases, and serine proteinase inhibitors. The metalloproteases and one proteinase inhibitor are related to blood proteinases but the other two inhibitors and serine proteinases seem to be unique for the reproductive tract.

Animals↗
PubMed2005

Spermatogenesis in the turkey (Meleagris gallopavo): quantitative approach in immature and adult males subjected to various photoperiods.

The objectives of this study were to identify and quantitate the germ cell populations of the testes in sexually mature male turkeys (Trial 1), determine the duration of meiosis based on BrdU labeling and stereological analyses (Trial 2), and examine the impact of various photoperiods on germinal and somatic cell populations in immature and adult males (Trial 3). In Trial 1, both testes within a male had similar stereological components (P>0.05) for all parameters analyzed. In Trial 2, the duration of Type-1 spermatocytes and round spermatids in turkeys lasted 4.5+/-0.5 and 2.0+/-0.5 days, respectively. In Trial 3, the short photoperiod (7L:17D) delayed testicular growth (in the stereological parameters analyzed). In contrast, the effect of a moderately short photoperiod (10.5L:13.5D) was comparable to the effect of a long (14L:10D) or increasing photoperiod (7L:17D to 14L:10D) on the stereological parameters examined. With the exception of the short photoperiod, all other photoperiods used in this study induced comparable early testicular maturation, with maximum testis weight at 29-35 weeks of age. As the males got older, there was a progressive, linear decline in testis weight through 60 weeks, at which time there were no significant differences among photoperiods. In conclusion, the duration of meiosis in the turkey was similar to that observed in the fowl and guinea-fowl. The existence of a threshold of photosensitivity to gonad stimulation in male turkeys is suggested to be between 7.0 and 10.5 h of light.

Aging↗
PubMed2005

CpG motifs as adjuvant in DNA vaccination against Chlamydophila psittaci in turkeys.

Plasmid DNA (pcDNA1::MOMP) expressing the major outer membrane protein (MOMP) of an avian Chlamydophila psittaci serovar D strain and recombinant MOMP (rMOMP) with or without the immunomodulating CpG oligonucleotides (CpG ON) were tested for their ability to elicit an immune response and to induce protection in turkeys against homologous challenge. Two CpG ON were chosen for in vivo application based on their in vitro capacity to stimulate the production of nitric oxide (NO) in chicken macrophages and their in vitro capacity to induce turkey lymphocyte proliferation. Priming and boosting of turkeys with pcDNA1::MOMP was able to prevent severe clinical signs and bacterial replication in a turkey model of C. psittaci infection. rMOMP boosting induced high antibody titers, but these did not correlate with the level of protection. Although the CpG ON induced a significant in vitro response, the presence of the CpG ON as an adjuvant generated no significant effect on the immune response or on the protective capacity of the tested vaccination methods.

Animals↗
PubMed2005

Key role of Chlamydophila psittaci on Belgian turkey farms in association with other respiratory pathogens.

Two hundred turkey sera from eight Belgian and two French farms were tested for the presence of antibodies against avian pneumovirus (APV), Ornithobacterium rhinotracheale (ORT), Mycoplasma gallisepticum, Mycoplasma meleagridis and Chlamydophila psittaci. At slaughter, C. psittaci, APV and ORT antibodies were detected in 94, 34 and 6.5% of the turkeys, respectively. No antibodies against M. gallisepticum or M. meleagridis were present. Additionally, turkeys on three Belgian farms were examined from production onset until slaughter using both serology and antigen or gene detection. All farms experienced two C. psittaci infection waves, at 3-6 and 8-12 weeks of age. Each first infection wave was closely followed by an ORT infection starting at the age of 6-8 weeks, which was still detectable when the second C. psittaci infection waves started. Animals on farm A were not vaccinated against APV leading to an APV subtype B outbreak accompanying the first C. psittaci infection wave. Despite subtype A APV vaccination on farms B and C, the second C. psittaci infection waves were accompanied (farm B) or followed (farm C) by a subtype B APV infection. On all farms respiratory signs always appeared together with a proven C. psittaci, APV and/or ORT infection. This study suggests an association between C. psittaci, APV and ORT, and indicates the multi-factorial aetiology of respiratory infections in commercial turkeys. All three pathogens should be considered when developing prevention strategies for respiratory disease.

Age Factors↗
PubMed2005

Utilization of turkey manure as granular activated carbon: physical, chemical and adsorptive properties.

The high availability of large quantities of turkey manure generated from turkey production makes it an attractive feedstock for carbon production. Pelletized samples of turkey litter and cake were converted to granular activated carbons (GACs) by steam activation. Water flow rate and activation time were changed to produce a range of activation conditions. The GACs were characterized for select physical (yield, surface area, bulk density, attrition), chemical (pH, surface charge) and adsorptive properties (copper ion uptake). Carbon physical and adsorptive properties were dependent on activation time and quantity of steam used as activant. Yields varied from 23% to 37%, surface area varied from 248 to 472 m(2)/g and copper ion adsorption varied from 0.72 to 1.86 mmol Cu(2+)/g carbon. Copper ion adsorption greatly exceeded the values for two commercial GACs. GACs from turkey litter and cake show considerable potential to remove metal ions from water.

Adsorption↗
PubMed2004

Turkey prolactin gene regulation by VIP through 35-bp cis-acting element in the proximal promoter.

Vasoactive intestinal peptide (VIP) has been shown to increase prolactin (PRL) gene expression and secretion in turkey primary anterior pituitary cells. To characterize cis-acting elements involved in stimulation of PRL gene expression by VIP, 5'-flanking deletions and/or mutations of the turkey PRL promoter fused to the luciferase (Luc) reporter gene have been constructed for use in transient transfection assays. Deletion analysis of the turkey PRL promoter (tPRLP) indicated that the VIP-stimulated tPRLP activity was controlled by three major positive regulatory regions and two negative regions. The -74/+40 Luc construct exhibited a 7- to 8-fold increase in promoter activity in response to VIP treatment. Deletion of the 35-bp segment (-74/-40) or fusion of this sequence to the SV40 promoter demonstrated that a VIP response element (VRE) was present in this region. Functional analysis of this VRE (-74/-40) was performed by mutation of core sequences (TGAATGTATGCA, -61/-50) or deletion of a 35-bp segment and a Decoy assay. Electrophoretic mobility shift assays revealed the presence of three DNA-protein complexes bound to the region -73 to -41. The results of the present study demonstrated that VRE (35-bp) in the proximal PRL promoter is an important cis-acting element for VIP-stimulated PRL gene expression in turkey primary anterior pituitary cells.

Animals↗