MODERN GENETICS JOURNAL (MGJ)
Year:2009 | Volume:3 | Issue:4|Papers Count:8

A mass spectrometer (MS) is an instrument that produces ions from analytes and separates them in the gas phase according to their mass-to-charge ratio (m/z). The technique has its origin from studies done by J. J. Thomson and his student F. W. Aston about the turn of the last century. Today MS is the most sensitive method for the structural characterization of biomolecules. Every mass spectrometer now consists of: an ion source, to produce ions from the sample; one or more mass analyzers, to separate the ions according to their m/z ratios; a detector, to register the number of ions emerging from the last analyser; and a computer, to process the data, to create the mass spectrum, and to control the instrument through feedback. Indeed mass spectrometry analysis of peptides and proteins relies on soft ionization techniques that create intact gas-phase ions from biomolecules. The two soft ionization techniques that most commonly used for the mass spectrometric analysis of proteins and peptides are Electrospray ionization (ESI) and Matrix-assisted laser desorption ionisation (MALDI). There are two main routes by which proteins are identified using MS. The classical proteomics approach involves the separation of the proteins in a mixture by two dimensional gel electrophoresis (2DE), followed by in-gel tryptic digestion and peptide mass fingerprinting (PMF) by MALDI-TOF MS. In this approach, proteins are identified by comparison of the experimentally determined peptide masses with the predicted mass values of the peptides generated by a theoretical digestion of each protein in a database. Another approach involves the use of tandem mass spectrometry (MS\MS) to obtain a short amino acid sequence (sequence tag) from protein, followed by database searching using sequence tag. Mass spectrometric methods can also be used to determine the type and site of post translational modifications (PTM) on single, purified protein.

Data on 3337 Kordi lambs that were collected over a period of 1993 to 2003 in Shirvan station of Kordi sheep, used to estimation of genetic and environmental trends. Considered traits were included birth weight (BW), weaning weight (WW), six month weight (6MW) and nine month weight (9MW). Genetic parameters and thus breeding values, required for estimation of genetic trend, were determined for each trait applying Derivative Free Restricted Maximum Likelihood procedures under uni-variate animal models. Six statistical models including different combinations of direct genetic, maternal genetic and maternal permanent environmental effects were fitted into each trait, using DFREML software. Likelihood ratio test was used to determine the most suitable model for each trait. The test indicates that the model including direct and maternal genetic effects, with covariance between them, was the most suitable model for BW. The model including direct genetic effects as well as, maternal permanent environmental effects was the most suitable one for WW and 6MW, The model including direct genetic effects as only random effect was the most suitable one for 9MW. Genetic trends were estimated by regressing the mean of breeding values on year. The additive genetic trends for BW, WW, 6MW and 9MW using univariate analysis were estimated 0.80±1.87, 72.90±16.97, 59.63±21.20 and 136.52±28.21 gr per year, respectively. The phenotypic trends for BW, WW, 6MW and 9MW were estimated 14.13±1.25, 69.50±35.1, 59. -90.53±68.12 and 133.32±65.24 gr per year, respectively the maternal genetic trend for BW was 4.90±2.22 gr per year. The environmental trends of traits, the differences between phenotypic and genetic trends, for BW, WW, 6MW and 9MW were -2.97±2.84, - 3.40±0.87, -150.15±89.10 and -3.20±11.30 gr per year, respectively.

Investigation of phylogenetic relationships within tribe Lycieae (Solanaceae), especially genus Lycium has been a case of research of interest in recent years. Because of Gender dimorphism in Lycium, it,s evolution is very important. Phylogenetic studies have mostly been based on South and North American species and some of species in Old world. For determination phylogeny of Old world taxa, Iranian species beside some species of New and Old world, and two genes of chloroplast and nuclear have been studied. Genus Lycium in IRAN were not monophyletic group and In contrast to some previous reports, the Old world species were polyphyletic group in this research.

A population consisting 59 advanced backcross lines (BC2F5) derived from a cross between IR64 and Tarom molaei, was studied in Chaparsar-Tonekabon Rice Research Station, Iran, in order to map the QTLs and determine the characteristics of QTLs for panicle length, number of full grain, number of empty grain, number of spiklet per panicle and grain sterility in rice. The parental polymorphisme was studied by 235 SSR markers in agarose and polyacrylamide gels, and 114 markers with clear polymorphic bands were selected for genotyping. Positive and negative transgressive segregationes were observed in BC2F5 lines for all traits. Using multiple interval mapping, 26 putative QTLs were detected, consisted eight for panicle length, three QTLs for number of spiklet, two QTLs for number of full grain, four QTLs for number of empty grain, and nine QTLs for grain sterility. More than 46 percent of QTLs had negative additive effects. The maximum number of QTLs were mapped in chromosomes 1 with six QTLs. Because of mapping more than one QTL for most traits, it is concluded that these traits are polygenic.

High rate of ovulation and litter size are the most important affecting factors in reproduction system and subsequently increases economical efficiency in sheep breeding industry. This study was carried out for detection of mutation in FecB and FecXI genes in Lori-Bakhtiari sheep breed. It has been reported that these major genes can increase ovulation and also twining rate in different sheep breed. Blood samples were collected from 165 individual for identification of polymorphisms at these loci. DNA was extracted using modified salting out method. Polymorphism chain reaction (PCR) was used to amplify desired fragments at these loci using two pairs of specific primers. Each of specified primer pairs amplified a fragment with 190 and 154 bp at FecB and FecXI loci, respectively. For genotyping of the samples, the PCR products were electrophoresed on 3% agarose gel after digestion with endonuclease AvaII for FecB and XbaI for FecXI. In the case of mutation, two fragments of 30, 160 and 30, 124 bp could be detected in FecB and FecXI loci, respectively. The genotyped samples at the present study did not confirm the incidence of mutant allele (-), since all samples showed monomorph (+/+) genotypes. Regarding the phonotypic record in this breed, the obtained results indicates that the genetic factor responsible for twining or multiple lambing rate is not related to reported mutated alleles at Booroola or Inverdel major genes and we should search for other genes in this breed.

In this research four CMS lines and four their maintainer counterparts were used for molecular studies. DNA from iso-cytoplasmic CMS and maintainer lines was amplified using 35 RAPD primers. PCR with these RAPDs showed that 5 primers could produce polymorphic bands between CMS line Neda-A and its maintainer Neda-B. To confirm precise association of the identified markers to male sterile or normal cytoplasm, DNA from further 6 CMS and respective maintainer lines were screened using the 5 polymorphic primers, among which only two primers OPC05 and OPH03 could amplify CMSspecific bands. The primers produced ~500bp and ~1900bp bands, respectively. The ~1900bp band was successfully cloned in pGEM-T vector and then sequenced. Several new primers were designed based on the sequenced fragment, and were used for detecting polymorphism between CMS and maintainer line. PCR with these SCAR primers indicated that a primer combination (SCARmt01-F – SCARmt01-R) could produce polymorphism between CMS and maintainer line. Also the combination of RAPD primers was resulted into the detection of polymorphism between CMS and maintainer line when OPA01 were combined with OPB04. Produced band by this primer combination was cloned, sequenced, and new three pairs of SCAR primers were designed according to the sequenced fragment. PCR with these specific primers was resulted into identification of a new co-dominant, specific SCAR marker with the ability of discriminating between CMS and maintainer line. The use of identified specific markers can accelerate progress of hybrid rice production program.

In order to determine genetic relative between triticale, tritipyrum and wheat genomes, genomic DNA of Thinopyrum bessarabicum (EbEb), triticale premising lines (AABBRR), tritipyrum primary lines (AABBEbEb), Chinese spring and breeding cultivars of wheat (AABBDD) were amplified using 25 semi random and 30 random primers. Bands that present in the Th. Bessarabicum, triticale premising lines and tritipyrum lines, but absent in the breeding and Chinese spring cultivars of wheat, assumed as shared bands between triticale (RR) and tritipyrum (EbEb) genomes. Jaccard coefficient of similarity used for determination of genetic relative of triticale (RR) and tritipyrum (EbEb) with wheat genomes. ET34 and ET37 of semi random and OPM06 of random primers could be amplified shared bands between triticale (RR) and tritipyrum (EbEb) genomes. From 238 bands that amplified by random and semirandom primers, 5 bands (2.2%) were shared between triticale (RR) and tritipyrum (EbEb) and 16.8% were shared between tritipyrum (EbEb) and wheat genomes. 4.02% of RAPD markers, were specified to tritipyrum (EbEb) genome. Average genetic similarity between triticale premising lines, tritipyrum primary lines, and Th. bessarabicum were 0.179, between tritipyrum primary lines and wheat breeding cultivars were 0.194 and between triticale premising lines and wheat breeding cultivars were 0.161. This study confirmed high homology of tritipyrum (EbEb) with wheat, relatively homology of triticale (RR) and tritipyrum (EbEb) genomes and usefulness of random and semi random primers in detecting chromatin/DNA fragment of intergeneric hybrids with durum wheat.