Population Genetic Structure of the Marine Penaeid Prawn- Penaeus Indicus H. Milne Edwards 1837

The thesis contains the results of an investigation on the " Population Genetic Structure of the Penaeus indicus " from southeast and southwest coasts of India. The P.indicus, popularly known as the Indian white prawn, is distributed widely in the Indo-Pacific, starting from New South wales in Australia in the east to the east coast of Africa in the west. Its heavy demand in the export market, the species has been exploited intensively from all along its areas of distribution in Indian waters. The population genetic characteristics of the species were examined by three independent but complementary techniques, namely, morphometrics (truss network), biochemical genetics (isozyme electrophoresis ) and molecular genetics (RFLP and RAPD). The east and west coast populations of the species may be genetically different. Due to certain constraints, the results obtained from the studies of restriction fragment length 70 polymorphism (RFLP) were limited. The significant difference in the number of bands in the sample populations strongly suggests that these two populations have considerably different population genetic structures

Studies on biochemical genetics of the grey mullet Mugil cephalus linnaeus

The thesis deals with the results of an investigation on the "BIOCHEMICAL GENETICS OF MUGIL CEPHALUS" from Cochin, Madras and Orissa. It is presented under the following major headings: Introduction, Review of Literature, Materials and Methods, Results, Discussions, Conclusions, Recommendations, Summary and References.The introduction gives a brief account of historical and modern back ground on the stock concept in fisheries research and management, followed by the importance and potential role of biochemical genetics in the identification of natural units of fisheries management. In the review of literature published reports relevant to biochemical genetics with special reference to that of general proteins and enzyme systems of fish populations were considered. A detailed account of the source of experimental specimens, mode of collection, transportation, sample extraction, gel preparation/gel electrophoresis, buffer systems, staining procedures of proteins/enzymes, standardization of experiments, interpretation of electrophoretic data using basic formulae etc. are given in the materials and methods section. Four important conclusions were drawn on the basis of the results of the present investigation. Three recommendations were also made on the basis of evaluation of the results.

Biochemical Genetics Of Selected Commercially Important Penaeid Prawns

���Biochemical genetics of selected commercially important penaeid prawns��� dloted was carried out by collecting samples from different important fishing ceatres of India and the practical work was carried out in the Research Centre of CMFRI laboratories attached with those places. On the whole, in crustacea little importance has been given so far in finding out tin genetic characteristics of different species, genetic variation within and between species and ontogenetic variations in lobsters, prawns and other crustaceans. Prawn is caunercially important group where very little attention had been given so far to find out the racial divergence which may exist in cufferent species. with the increased foreign exchange earning and consequent indiscriminate over exploitation of existing resources of prawns resulting in depletion of the marine rescurces, alternative ways and augmenting production has become essential. In this connection genetic manipulation of the broodstock will surely bring about the heterogenous characters to multiply production. In order to understand racial fragmentation of sane of the coumercially important prawns such as Pengeus ggdicus and Parggenagsis sgliferg the isozyme studies were carried out. Qatogenetic variation of g. indicus showed stage specific electrophoretic variation. Inter species variation studies was carried out for the closely aligned Penaeus species

Crocidura cossyrensis Contoli, 1989 (Mammalia, Soridiae): karyotype, biochemical genetics and hybridization experiments

Crocidura cossyrensis Contoli, 1989 (Mammalia, Soricidae): karyotype, biochemical genetics and hybridization experiments. - The shrew Crocidura cossyrensis Contoli, 1989 from Pantelleria (I), a Mediterranean island 100 km south of Sicily and 70 km west from Tunisia, was investigated in order to understand its origin and its relationship with C. russula from Tunisia, Morocco and Switzerland. With the exception of a single heterozygote centric fusion, C. cossyrensis had a karyotype identical with that of C russula from Tunisia (2N = 42, NF = 70 to 72), but it differed from C russula from Morocco and Switzerland (2N = 42, NF = 60). The former have 5-6 pairs of chromosomes with small arms that are acrocentric in the latter. Genetic comparisons with allozyme data revealed small genetic distance (0.04) between C cossyrensis and C russula from Tunisia. In contrast, this eastern clade (Tunisia and Pantelleria) is separated from the western clade (Switzerland and Morocco) by a genetic distance of 0.14. A hybridization experiment between shrews from Pantelleria and Switzerland lead rapidly to an F1 generation. From 12 F1 hybrids that were backcrossed, females reproduced normally, but none of the males did so. Concluding from the results, C. cossyrensis from Pantelleria and C. russula cf. agilis from Tunisia belong to the same taxon that may have reached the differentiation of a biological species within the C. russula group. More geographic samples are needed to determine the definitive taxonomic positions of these shrews.

Polimorfismos del gen Butirilcolinesterasa responsables de reacciones adversas en pacientes consumidores de ���coca��na���

La butirilcolinesterasa humana (BChE; EC 3.1.1.8) es una enzima polim��rfica sintetizada en el h��gado y en el tejido adiposo, ampliamente distribuida en el organismo y encargada de hidrolizar algunos ��steres de colina como la proca��na, ��steres alif��ticos como el ��cido acetilsalic��lico, f��rmacos como la metilprednisolona, el mivacurium y la succinilcolina y drogas de uso y/o abuso como la hero��na y la coca��na. Es codificada por el gen BCHE (OMIM 177400), habi��ndose identificado m��s de 100 variantes, algunas no estudiadas plenamente, adem��s de la forma m��s frecuente, llamada usual o silvestre. Diferentes polimorfismos del gen BCHE se han relacionado con la s��ntesis de enzimas con niveles variados de actividad catal��tica. Las bases moleculares de algunas de esas variantes gen��ticas han sido reportadas, entre las que se encuentra las variantes At��pica (A), fluoruro-resistente del tipo 1 y 2 (F-1 y F-2), silente (S), Kalow (K), James (J) y Hammersmith (H). En este estudio, en un grupo de pacientes se aplic�� el instrumento validado Lifetime Severity Index for Cocaine Use Disorder (LSI-C) para evaluar la gravedad del consumo de ���coca��na��� a lo largo de la vida. Adem��s, se determinaron Polimorfismos de Nucle��tido Simple (SNPs) en el gen BCHE conocidos como responsables de reacciones adversas en pacientes consumidores de ���coca��na��� mediante secuenciaci��n del gen y se predijo el efecto delos SNPs sobre la funci��n y la estructura de la prote��na, mediante el uso de herramientas bio-inform��ticas. El instrumento LSI-C ofreci�� resultados en cuatro dimensiones: consumo a lo largo de la vida, consumo reciente, dependencia psicol��gica e intento de abandono del consumo. Los estudios de an��lisis molecular permitieron observar dos SNPs codificantes (cSNPs) no sin��nimos en el 27.3% de la muestra, c.293A>G (p.Asp98Gly) y c.1699G>A (p.Ala567Thr), localizados en los exones 2 y 4, que corresponden, desde el punto de vista funcional, a la variante At��pica (A) [dbSNP: rs1799807] y a la variante Kalow (K) [dbSNP: rs1803274] de la enzima BChE, respectivamente. Los estudios de predicci��n In silico establecieron para el SNP p.Asp98Gly un car��cter patog��nico, mientras que para el SNP p.Ala567Thr, mostraron un comportamiento neutro. El an��lisis de los resultados permite proponer la existencia de una relaci��n entre polimorfismos o variantes gen��ticas responsables de una baja actividad catal��tica y/o baja concentraci��n plasm��tica de la enzima BChE y algunas de las reacciones adversas ocurridas en pacientes consumidores de coca��na.

Variation of genetic expression during development, revealed by esterase patterns in Aedes aegypti (Diptera, Culicidae)

Polyacrylamide gel electrophoresis was used to analyze esterase patterns during development of Aedes aegypti from the cities of Mar��lia and S��o Jos�� do Rio Preto (SJRP), Brazil. The zymograms showed a total of 23 esterase bands, 22 of which were in the specimens from Mar��lia and 19 in those from SJRP. These esterase bands were considered to be the product of 23 alleles distributed tentatively in eight genetic loci. Most of the alleles were developmentally regulated. The larval stage expressed the greatest number of them (19 alleles, from the eight loci, in Mar��lia; and 17 alleles, from seven loci, in SJRP). The pupal stage expressed 10 alleles from seven loci, in both populations, and the adult stage expressed 8 alleles from five and six loci in SJRP and Mar��lia, respectively. Some alleles that were active in every stage were developmentally controlled at the level of expression (amount of product). A single allele was constitutively and highly expressed, in larvae, pupae, and adults, in both populations. Differences in esterase synthesis among stages are probably due to regulatory mechanisms acting in agreement with the requirements of a variable number of processes in which esterases are involved. The larval stage is the most active in developmental processes and shows very intense intake of food and very high mobility. These features may demand increased esterase production at that stage. Comparison of the two populations examined showed (besides the existence of alleles that they do not share) that they exhibit differences in the control of expression of other alleles. Such findings may reflect genetic differences between founders in each population, but the possibility of involvement of the intensive use of insecticides in SJRP is also discussed.

Microsatellite Polymorphisms in Cassava Landraces from the Cerrado Biome, Mato Grosso do Sul, Brazil

Using nine microsatellite loci, we investigated genetic structure and diversity in 83 Brazilian cassava accessions, including several landraces, in the Cerrado biome in Mato Grosso do Sul, Brazil. All nine loci were polymorphic, averaging 6.00 alleles per locus. Treating each of seven municipalities as a cassava group or population, they averaged 3.5 alleles per locus, with 97% polymorphic loci, high values for observed heterozygosity (0.32) and gene diversity (0.56). Total genetic variability was high (0.668), and most of this genetic variability was concentrated within municipalities (0.577). Cluster and structure analyses divided accessions into two major clusters or populations (K = 2). Also, a significant genetic versus geographic correlation was found (r = 0.4567; P < 0.0260). Migratory routes in the Cerrado are considered main contributors to the region`s high cassava diversity and spatial genetic structure, amplifying interactions between traditional farmers and the evolutionary dynamics of this crop.

A single amino acid substitution in one of the lipases of Aspergillus nidulans confers resistance to the antimycotic drug undecanoic acid

A plausible approach to evaluate the inhibitory action of antifungals is through the investigation of the fungal resistance to these drugs. We describe here the molecular cloning and initial characterization of the A. nidulans lipA gene, where mutation (lipA1) conferred resistance to undecanoic acid, the most fungitoxic fatty acid in the C(7:0)-C(18:0) series. The lipA gene codes for a putative lipase with the sequence consensus GVSIS and WIFGGG as the catalytic signature. Comparison of the wild-type and LIP1 mutant strain nucleotide sequences showed a G -> A change in lipA1 allele, which results in a Glu(214) -> Lys substitution in LipA protein. This ionic charge change in a conserved LipA region, next to its catalytic site, may have altered the catalytic properties of this enzyme resulting in resistance to undecanoic acid.

Genetic variability among populations of Lutzomyia (Psathyromyia) shannoni (Dyar 1929) (Diptera: Psychodidae: Phlebotominae) in Colombia

Polyacrylamide gel electrophoresis was used to elucidate genetic variation at 13 isozyme loci among forest populations of Lutzomyia shannoni from three widely separated locations in Colombia: Palamb�� (Nari��o Department), Cimitarra (Santander Department) and Chin��cota (Norte de Santander Department). These samples were compared with a laboratory colony originating from the Magdalena Valley in Central Colombia. The mean heterozygosity ranged from 16 to 22%, with 2.1 to 2.6 alleles detected per locus. Nei's genetic distances among populations were low, ranging from 0.011 to 0.049. The estimated number of migrants (Nm=3.8) based on Wright's F-Statistic, F ST, indicated low levels of gene flow among Lu. shannoni forest populations. This low level of migration indicates that the spread of stomatitis virus occurs via infected host, not by infected insect. In the colony sample of 79 individuals, the Gpi locus was homozygotic (0.62/0.62) in all females and heterozygotic (0.62/0.72) in all males. Although this phenomenon is probably a consequence of colonization, it indicates that Gpi is linked to a sex determining locus.

Isozymic variability in a Brazilian collection of annatto (Bixa orellana L.)

The objectives of this work were to optimize the isozyme electrophoresis technique for Bixa orellana, and use isozyme markers for a preliminary survey on the genetic variability in Brazilian annatto germplasm accessions. Collection consisted of seed samples from sixty open pollinated trees, representing two Northern and four Southern geographic provenances. The extraction, electrophoresis, and interpretation of annatto isozymes are described. Three out of the twenty-one identified isozyme loci were polymorphic in the collection. The percentage of polymorphic loci (P = 21.05) and the expected heterozygosity in annatto (H T = 0.064) were low, compared to other tropical woody species. A UPGMA phenogram, constructed with Nei's genetic distances, clearly separated the germplasm provenant from North and Central Brazil. Variability was significantly higher among the accessions from Maranh��o. A sharp genetic differentiation was detected between accessions from Maranh��o and Par�� States, despite their geographical proximity. The distinctive isozyme polymorphism, observed in the accessions from Maranh��o, together with reports on local morphological heterogeneity in annatto fruit shape, color, and pubescence, calls for more detailed genetic and taxonomic investigation.

Genetic variation in the European hake, Merluccius merluccius. Description of protein loci and genetic divergence between Atlantic and Mediterranean populations = An��lisi de la variabilitat gen��tica en el llu�� europeu, Merluccius merluccius. Descripci�� dels loci electrofor��tics i diverg��ncia gen��tica entre les poblacions atl��ntica i mediterr��nia

We examined the genetic population structure of the european hake (Merluccius merluccius) using electrophoretically detectable population markers in 35 protein loci. Samples were collected from 7 locations in the Atlantic Ocean and Mediterranean Sea. Six loci were polymorphic using the 0.05 criterion of polymorphism. Sample heterozigosities ranged from 0.052 to 0.072 and averaged 0.0625. In this study, significant allele frequency differences were detected between Atlantic and Mediterranean populations in three polymorphic loci: GAPDH-1*, GPI-2* and SOD-1*. Two major genetic groups were considered: a North-Atlantic stock and the Mediterranean stock. The Nei genetic distance, D, (based on 33 loci) between samples from these two groups ranged from 0.002 to 0.006. Genetic differenciation between these areas appears to reflect the barrier effect of Strait of Gibraltar. On average over loci, 96.92 % of the total gene diversity was contained within samples, 0.23 % expressed differences among locations within areas, and 2.64 % differences between regions. A review of morphological variation together with the genetic data presented here suggest that the populations of hake from these areas are subdivided into two different stocks: the North-Atlantic stock and the Mediterranean stock. The most conservative approach to the management of these stocks is to consider the Atlantic and Mediterranean stocks independently from oneanother

Physiopathologie des maladies m��taboliques h��r��ditaires des acyls-Coenzyme A r��v��l��e par l�����tude d���un mod��le animal d��ficient en 3-hydroxy-3-m��thylglutaryl-Coenzyme A lyase

La plupart des conditions d��tect��es par le d��pistage n��onatal sont reli��es �� l'une des enzymes qui d��gradent les acyls-CoA mitochondriaux. Le r��le physiopathologique des acyls-CoA dans ces maladies est peu connue, en partie parce que les esters li��s au CoA sont intracellulaires et les ��chantillons tissulaires de patients humains ne sont g��n��ralement pas disponibles. Nous avons cr���� une mod��le animal murin de l'une de ces maladies, la d��ficience en 3-hydroxy-3-methylglutaryl-CoA lyase (HL), dans le foie (souris HLLKO). HL est la derni��re enzyme de la c��togen��se et de la d��gradation de la leucine. Une d��ficience chronique en HL et les crises m��taboliques aig��es, produisent chacune un portrait anormal et distinct d'acyls-CoA h��patiques. Ces profils ne sont pas pr��visibles �� partir des niveaux d'acides organiques urinaires et d'acylcarnitines plasmatiques. La c��togen��se est ind��tectable dans les h��patocytes HLLKO. Dans les mitochondries HLLKO isol��es, le d��gagement de 14CO2 �� partir du [2-14C]pyruvate a diminu�� en pr��sence de 2-ketoisocaproate (KIC), un m��tabolite de la leucine. Au test de tol��rance au pyruvate, une mesure de la glucon��ogen��se, les souris HLLKO ne pr��sentent pas la r��ponse hyperglyc��mique normale. L'hyperammoni��mie et l'hypoglyc��mie, des signes classiques de plusieurs erreurs inn��es du m��tabolisme (EIM) des acyls-CoA, surviennent de fa��on spontan��e chez des souris HLLKO et sont inductibles par l'administration de KIC. Une charge en KIC augmente le niveau d'acyls-CoA reli��s �� la leucine et diminue le niveau d'ac��tyl-CoA. Les mitochondries des h��patocytes des souris HLLKO trait��es avec KIC pr��sentent un gonflement marqu��. L'hyperammoni��mie des souris HLLKO r��pond au traitement par l'acide N-carbamyl-L-glutamique. Ce compos�� permet de contourner une enzyme ac��tyl-CoA-d��pendante essentielle pour l���ur��ogen��se, le N-ac��tylglutamate synthase. Ceci d��montre un m��canisme d���hyperammoni��mie li�� aux acyls-CoA. Dans une deuxi��me EIM des acyls-CoA, la souris SCADD, d��ficiente en d��shydrog��nase des acyls-CoA �� cha��nes courtes. Le profil des acyls-CoA h��patiques montre un niveau ��lev�� du butyryl-CoA particuli��rement apr��s un je��ne et apr��s une charge en triglyc��rides �� cha��ne moyenne pr��curseurs du butyryl-CoA.

POPULATION GENETIC STUDIES ON THE OIL SARDINE ( Sardinella longiceps )

The objective of present investigation was to study the population genetic structure of S. longiceps by applying three different basic population genetic techniques such as cytogenetics, non-enzymatic biochemicalgenetics (general protein) and morphomeristics/metrics.