IRANIAN JOURNAL OF BIOLOGY
Year:2004 | Volume:17 | Issue:2|Papers Count:9

CpDNA variation in the oriental beech, Fagus orientalis Lipsky (Fagaceae) was studied in 14 populations distributed throughout the species range in Hyrcanainzone, Iran. Two cpDNA intergenicregionswere analyzed:(i) DT region between trnD (tRNA-Aspand trnT (tRNA-Thr) genes, and (ii) OA region between the orj184 and petA genes. The restriction fragments of the region DT did not show any polymorphism among individuals within any analyzed populations. However, among individuals within analyzed populations of Asalem and Neka-1400, polymorphismin the restriction fragments of the OA regionwas found.A total of 3 different chloroplast (cp) haplotypes were scored. The distribution of the cpDNA haplotypes revealed a geographical structure of the genetic differentiation with Gst=%68.7 and Nst=%70.3. The distribution pattern of F orientalis cpDNA haplotypes may reflect environmental differences and migration history of beech during historical distribution in Tertiary from Asalem (most polymorphic zone) to east part of Hyrcanian forests.

The cell walls of some dicotyledonous plants (pear, tomato, apple etc.) and a few monocotyledonous plants contain a polygalacturonase-inhibiting protein (PGIP) that binds to and inhibits fungal endopolygalacturonase. PGIP has a great potential for limiting fungal colonization by acting as both inhibitors and regulators of fungal polygalacturonases activity and by favoring the release of oligogalacturonide (OG) fragments, which are elicitors of a variety of defense responses. In this study, inhibitory effect of PGIP extracted from Phaseolus vulgaris cv. Derakhshan on polygalacturonase enzyme of Fusarium oxysporum was analyzed. PG enzyme was isolated from highly virulent isolate of F. oxysporum (F15). The PG activity was inhibited by hypocotyle PGIP about 54.5%.For pgip gene amplification, genomic DNA from leaves were used. The expected PCR product (1047 bp) was amplified with specific primers, which contain appropriate site for cloning. The PCR product was confirmed by restriction digestion. Pgip gene (1029 bp) was subcloned into pUC18 vector. The sequence of the cloned gene was aligned with related DNA sequences in the GeneBank. The results showed 100% similarity of this sequence to pgip-l of Phaseolus vulgaris cv. Saxa. There was differed in 26 nt from pgip-2 sequence from Phaseolus vulgaris cv. Pinto.

Xho1 enndonuclease are purified from a local strain of Xantomonas vasicola pv. holcicola by streptomycin sulfate fractionation and phosphocellulose and DEAE cellulose column chromatography. Purified enzyme contained no detectable exo or endonucleolytic activity against Xv.pv.holcicola DNA.However,with native plasmid pTEM DNA as substrate, the enzme produced a linear double stranded DNA molecule. Xhol endonuclease activity caused a rapid decrease in the specific viscosity of a variety of foreign native DNAs. The specific viscosity of X V.pv.holcicola DNA was not altered under the same conditions. This enzyme recognizes hexanucleotides of palidromic sequence 3CTCGAG 5 and cuts into the same sequence between C-T Xhol endonuclease has an opitmum tempreture of 37°c with pH optima of 7.5 to 8.Xho1 endonuclease activity is remarkably inhibited above a NaCl concentration of 150mM,its activity is also severly impaired if N6-Mtyl adenine or 5-metyl cytosine are present in the recognition site. Optimum reaction conditions occur in a buffer which contains 50 mm Tris- HCL.PH=7.5,1OmMmg Ch lOOMmNaCI,lMmDTE.

There are many evidences, that estrogen influence the concentration of lipids and lipoproteins in serum and in liver. We studied the effects of ethinyl estradiol on concentrations of serum lipids and lipoproteins in hypercholesterolemic female rats. The rats were fed with a high cholesterol diet (2%) for a period of two months. Estradiol was injected subcutaneously daily. Finally blood samples were taken and the concentrations of total cholesterol, triglyceride, HDL, LDL, VLDL and AI (atherogenic index) were measured. Statistical evaluation was carried out using Duncan's test. The results suggest that ethinyl estradiol decreases the concentration of serum total cholesterol and LDL significantly (P<0.05), but doest change the triglyceride and VLDL. It has also no effect on HDL.

Angiotensin converting enzyme inhibitors like captopril can induce a persistant cough in man and some workers have suggested a role for bradykinin in precipitation of ACEI-induced cough. Noscapine is an alkaloid obtained from opium .It is effective in the treatment of Angiotensin converting enzyme inhibitors induced cough. It has reported that noscapine decreases the bradykinin effects. Bradykinin in the CNS that would trigger the release of NO, NA ,Ach ,excitatory amino acids and vasopressin which are involved in memory and cognition. In this study we investigated the central effects of different doses of noscapine on short-term and long term- memory and learning in rat. In the one-trial passive avoidance test in rat noscapine significantly dose dependently decreased the retention time when was injected at doses of (1,2,3µg/3µl,i.c.v)30 min before acquisition or 20 min or also 24hr before retentiontime. Also when Captopril(5µg/3µl,i.c.v) was injected alone 30 min before acquisition or 20 min or also 24hr before retention time prolonged the retention time .In addition ,coadministration of noscapine (l,2,3µg/3µl,i.c.v) and captopril(5µg/3µI,i.c.v ) at the same time impaired the retention time of rat.Therefore it is possible that noscapine impairs learning and memory by blocking the effect of bradykinin receptor activation.

The Rana ridibunda is presented in Anzali wetland and its adjacent rivers and lakes with different density. In this region was not any biological and ecological data about it up to now in. In this paper were studied the diet of tadpole and adult frog and its reproduction. For determination of tadpole diet there were studied 66 intestinal contents of tadpoles and compared with frequency of plankton surroundings. The first and end parts of 49 tadpole intestinal contents were surveyed for determination of absorbed planktons also there were studied 142 stomach of frog for consumed preys. There were field observations and females sampling for reproduction activities.The results showed that Chrysophyta from phytoplankton and Rotatoria from zooplankton had the most abundant than other plankton groups in nature and intestine however there was a rare similarity in the identified genus. There was not positive relation between tadpole length and weight classes with intestinal plankton abundance.The abundance of Chrysophyta had significant difference at first and end parts of intestinal contents, also the Chlorophyta and Rhizopoda phylums had a high decrease.Generally the abundance of Cocconeis, Cyclotella, Diatoma, Chlorella and Arcella genus had significant difference in two parts of tadpole intestinal contents.Also the result of frog diet showed that the average ratio of stomach contents weight to body weight was 2.94 percent. The most abundant of consumed preys were terrestrial insects, the aquatic insects and their larva were following ranks in the food composition.The field observations showed that reproduction and breeding activity is started in March at North and continued until August in South of Anzali wetland. The average of clutch size was about 5019± 2776 ova from 18 studied females. The metamorphosed specimens appears in early June and was seen until Nov. in many regions.

In this study, in vitro grown calluses of M. sativa were exposed to DV-C for 0,15, 30, and 60 min, and then, were transferred to MS medium containing 0, 2, 5, 10, 20, 30% PEG, and all explants were kept in the dark in the culture room. The tolerant calluses to osmotic stress were selected according to the fresh weight. Results showed that radiation of DV-C for 60 minute increased the osmotic tolerance and decreased the effect of drought stress in medium containing 10 and 20% PEG. A Pase activity was decreased under DV-C radiation while the activity of this enzyme was increased in unradiated calluses up to 20% concentration of PEG in the medium. However, it seems that DV-C radiation has activated endogenous plant defense system and may induced the expression of certain genes along the pathway of phenolic derivatives synthesis.