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We report the protein isolation, cloning and characterization of members of an unusual protein family, which comprise the most abundant proteins present in the squid eye. The proteins in this family have a range of molecular weights from 32 to 36 kDa. Electron microscopy and detergent solubilization demonstrate that these proteins are tightly associated with membrane structures where they may form tetramers. Despite this, these proteins have no stretches of hydrophobic residues that could form typical transmembrane domains. They share an unusual protein sequence rich in methionine, and contain multiple repeating motifs. We have therefore named these proteins Methionine-Rich Repeat Proteins (MRRPs). The use of structure prediction algorithms suggest very little recognized secondary structure elements. At the time of cloning no sequence or structural homologues have been found in any database. We have isolated three closely related cDNA clones from the MRRP family. Coupled in vitro transcription/translation of the MRRP clones shows that they encode proteins with molecular masses similar to components of native MRRPs. Immunoblot analysis of these proteins reveals that they are also present in squid brain, optic lobe, and heart, and also indicate that MRRP-like protein motifs may also exist in mammalian tissues. We propose that MRRPs define a family of important proteins that have an unusual mode of attachment or insertion into cell membranes and are found in evolutionarily diverse organisms.

27 páginas, 11 figuras, 7 tablas, The population biology of Loligo vulgaris and Loligo forbesi in Galician waters is described based on monthly samples from the fishery obtained during the period February 199 l-June 1992. Maturity was assessed using a maturity scale and indices. The estimated number of oocytes in mature females varied from 782 to 21 885 in L. vulgaris and from 1317 to 14 956 in L. forbesi, and showed a slight positive correlation with the length of the mantle (ML) for both species. Oocytes in the ovaries fall into three discrete size classes, which suggests that L. vulgaris and L.forbesi are intermittent or multiple spawning species. In L. vulgaris males mature at two different modal sizes, hence perhaps at two different ages, while in L. forbesi this occurs in both males and females. Males mature earlier in the season than females in both species. The maximum number of spermatophores found was 1010 and 1000 in two L. vulgaris males with 119 mm and 400 mm ML respectively, and 1035 in a L. forbesi male with 150 mm ML. In both species, spermatophore length increases with ML. Loligo forbesi males maturing at a larger size produce fewer but larger spermatophores than those maturing at a small size. Loligo vulgaris spawn throughout the year, but the period of more intensive spawning extends from December to April. The breeding season ofL. forbesi extends from December to May, the more intensive spawning extending from December to February. Sex ratios were variable for both species. Age and growth for both species and sexes were estimated by examining growth increments in the statoliths. Like-sized individuals had different ages in both species. The life span of L. vulgaris was estimated at about l year while L. forbesi seems to reach an age of 15-16 months. A list of prey species found in gastric contents of both species is given. The diet of L. vulgaris comprises fish (86.8%), cephalopods (6.0%), crustaceans (3.0%) and polychaetes (1.8%), and the diet of L. forbesi includes fish (75.6%), crustaceans (18.5%) and cephalopods (4.4%)., This work was funded by the Commission of the European Communities within the frame of this EEC research programme in the fisheries sector (FAR, contract no. MA 1.146).

Dissertação de mest., Biologia Marinha, 2007, Universidade do Algarve, Faculdade de Ciências do Mar e do Ambiente In order to protect and sustainably manage fishery resources, it is essential to understand the temporal and spatial utilization of habitats of the target species. A Geographic Information System and length frequency analysis were used, in both fishery and survey data, to detect Loligo forbesi migration patterns from west to east coast of Scotland and inshore-offshore movements. Although the migration between west coast and North Sea is not evident, it is possible that veined squid performs an inshore movement in summer/autumn and offshore in winter/spring to complete their life cycle. Two distinct migratory behaviours between the two cohorts of Scottish veined squid is also a possibility, one cohort can be resident in inshore waters while the other migrates to offshore waters in winter and spring. The environmental reasons for such movements were examined using a generalized additive mixed model (GAMM) that suggested that distance to coast is the most important variable affecting size distribution in almost all seasons; however abundance distribution seems to be influenced with the same importance by sea surface temperature, depth and distance to coast. L. forbesi also revealed an optimal peak of abundance in waters at ~11oC, 200m depth and 25miles far from coast. De modo a proteger e gerir de forma sustentável os recursos pesqueiros é essencial compreender como as espécies alvo utilizam os seus habitats temporal e espacialmente. Na lula riscada (Loligo forbesi) da Escócia isto é bastante importante uma vez que não existe qualquer medida de gestão da sua pesca, além do tamanho mínimo da malha das redes de arrasto. L. forbesi, encontra-se principalmente em águas costeiras, e nas águas escocesas apresenta duas coortes com dois períodos de desova e duas épocas de recrutamento. Diferentes estudos demonstraram que várias espécies de lulas fazem migrações de curta escala, de perto para longe da costa, e de grande escala, Este-Oeste ou Norte-Sul, e.g. a L. forbesi de Inglaterra. Estas movimentações poderão ser causadas por condições ambientais, nomeadamente pela temperatura e pela profundidade, uma vez que a abundância de várias espécies de lulas é influenciada por estas mesmas condições ambientais. Deste modo, os objectivos da presente tese são (1) verificar se L. forbesi faz migrações da costa Oeste para a costa Este da Escócia, no Inverno, para desovar e da costa Este para a Oeste, na Primavera, tal como sugerido por estudos anteriores; (2) detectar as eventuais migrações da L. forbesi da Escócia para zonas afastadas da costa e caso estes movimentos existam, verificar qual a sua relação com o ciclo de vida da espécie e; (3) verificar quais as razões ambientais que levam as lulas a migrar, dando ênfase à sua relação com a temperatura superficial do mar (SST), profundidade e distância à costa. Para testar as hipóteses, foram utilizados dados de cerca de 20 anos da espécie L. forbesi, fornecidos pelo Fisheries Research Services, provenientes de desembarques comerciais e de navios de investigação. Estes foram primeiro utilizados num Sistema de Informação Geográfica (SIG) e em análises de frequência de comprimentos para verificar a existência de uma migração entre a costa Este e Oeste da Escócia. Estas análises demonstraram que a migração entre a costa Oeste e Este não é evidente, mas comportamentos migratórios diferentes entre coortes podem ocorrer, uma vez que alguns dos mapas de SIG exibem dois picos distintos de abundância em certos anos e meses. Outra explicação pode ser que a população de L. forbesi de Inglaterra, migre em certos anos mais para Norte que o habitual entrando no território escocês devido a condições ambientais mais favoráveis. Os mesmos dados foram utilizados para construir gráficos de abundância e frequência de comprimentos contra a distância à costa onde os arrastos foram feitos. Estes gráficos mostram que é possível que esta espécie migre para águas costeiras no Verão e Outono e para águas mais longínquas durante o Inverno e Primavera, com a finalidade de completar o seu ciclo de vida. A coorte que desova no Verão deverá fazê-lo em zonas costeiras assim como o seu recrutamento no Outono. Contudo, o local de desova da coorte de Inverno e as áreas de recrutamento na primavera não são claros. A hipótese de dois comportamentos migratórios distintos entre as duas coortes de L. forbesi da Escócia é também uma possibilidade: enquanto uma coorte é residente em águas costeiras a outra migra para longe da costa durante o Inverno e a Primavera, ou chega a estas águas longe da costa vindo de áreas ainda mais distantes como os Rockall Banks. As razões ambientais para tais movimentos foram examinadas em R, com um modelo aditivo generalizado misto (GAMM), uma extensão do GAM, e com uma componente temporal (ano) como variável aleatória. Esta análise demonstrou que a distância à costa é a variável mais importante a afectar a distribuição por tamanhos, contudo, a distribuição da abundância parece ser influenciada igualmente pela SST, profundidade e distância à costa. A relação entre cada uma destas variáveis ambientais e o comprimento do manto da espécie em estudo varia consoante a estação do ano: e.g. no Inverno e Primavera quanto maior for o comprimento do manto mais próximo da costa se encontram as lulas, contudo, no Verão esta relação parece ser inversa. A influência destas variáveis na abundância é bastante uniforme ao longo dos diferentes meses: quanto menor a distância à costa maior será a abundância de lulas, até aos 200m de profundidade, quanto maior é a profundidade maior é a abundância e a abundância tem ainda um pico em águas com cerca de 10ºC. L. forbesi revelou, deste modo, ter um possível óptimo ambiental em águas escocesas com aproximadamente 10oC, 200m de profundidade e próximo da costa.

13 páginas, 7 figuras, 2 tablas, The reproductive pattern of Loligo vulgaris and Loligo forbesi was studied on the basis of gonad maturation, mating and spawning in males and females of both species which were present off the northwest coast of Spain (Galicia), between February 1991 and February 1993. The mature females of both species have several modes of egg sizes and developmental stages within the ovary. Several signs indicate that both female Loligo vulgaris and L. forbesi undergo partial ovulation at the time of spawning, the spawning period being relatively long, although in no case representing the greatest fraction of the animal's life before death. Egg-laying occurring in separate batches and somatic growth between egg batchs has not been observed. This reproductive pattern is defined as intermittenterminaspawning. Some other terms describing different cephalopod reproductive strategies are also defined., This work was financed by two projects under the auspices of the European Union (FAR, MA.1.146 and AIRl-CT92-0573).

22 páginas, 3 figuras, 17 tablas, 1 apéndice, Morphometric variation in the squid Loligoforbesi was investigated to quantify effects of region, season, sex and maturity. Practical exercises were carried out using this species and the congeneric Loligo vulgaris to evaluate differences in measurements by different workers. The utility of meristic characters was also examined. Consistent significant differences were found between measurements by different workers, although this problem may be reduced with experience and many of the differences were small compared with observed differences between areas, particularly differences between Loligoforbesi from the Azores and elsewhere (Scotland, Spain, Portugal). Body shape in Loligoforbesi varied significantly in relation to maturity stage and, to a lesser extent, with season. Multivariate analysis of morphometric characters for samples collected in Scottish waters over 12 months revealed no consistent differences between localities. In contrast, there were marked differences between Loligoforbesi from the Azores and those from UK waters. If future studies on geographic variation in loliginids are to make use of morphometric characters, they should be based on simultaneous sampling to minimise effects of season and maturity, and all measurements on a single character should be made by a single worker., This work was funded by the Commission of the European Communities within the frame of the EEC research programme in the fisheries sector (FAR, Contract No. MA 1.146). Data collection by AG and FGH in 1989 was supported by the Spanish Ministry of Education and Science and the British Council under the British/Spanish Joint Research Programme (Acciones Integradas 1989/90).

14 páginas, 9 figuras, 1 tabla, The Spanish fishery for the loliginid squids Loligo vulgaris and Loligo forbesi is described, with particular emphasis on the period 1983-1991. During this period the landings of squid in Spain stayed at a relatively constant level of around 2200 t. The value of the Spanish squid landings increased throughout the 1980s and amounted to £9.7 million in 1991. The two species of squid are not treated separately in the official statistics, and therefore the percentage corresponding to each is unknown; nevertheless, in the maritime regions of the Mediterranean, L. vulgaris is practically the only species landed, while in Atlantic regions, both are landed, although L. vulgaris is more abundant than L. forbesi. Particular attention is paid to the analysis and description of fisheries and squid landings in Galicia (northwest Spain) and Catalonia (northeast Spain), during the period 1980- 1991. In both regions, part of the landings correspond to trawling and purse-seine fisheries targeting finfish, where squid is caught as a by-catch. There are also important seasonal artisanal fisheries where the target species is squid. Landings have shown a marked seasonality; being more plentiful in summer and autumn. This resource does not show signs of overfishing. The present methods of fishing management are discussed, and proposals are put forward to modify some of these in order to avoid catching immature individuals of less than 200 mm mantle length., This work was funded by the Commission of the European Communities within the frame of this EEC research programme in the fisheries sector (FAR, contract no. MA. 1.146)

The squid (Loligo forbesi) visual system presents as accessible a system for study of G-protein mediated signal transduction as the vertebrate rod outer segment with the added advantage that the major G-protein is a member of the Gq-class. Here the cDNA clone encoding the gamma-subunit of this G-protein is reported, thereby completing the molecular cloning of the heterotrimeric G-protein. The deduced protein structure of G-gamma has relatively little sequence identity with known mammalian counterparts particularly in comparison with the relatively high degree found for both the alpha- and beta-subunits of this protein. In particular, the N-terminus of the squid visual G-gamma contains a repetitive, highly charged region, rich in lysine and glutamate, that has no parallel in other G-proteins. The amino acid sequence of a number of peptides derived by chemical cleavage of G-gamma accounted for much of the protein sequence predicted from the cDNA, including the unusual N-terminal region.

Johann Heinrich von Thunen-Institute, Federal Research Institute for Rural Areas, Forestry and Fisheries began publishing the Informationen aus der Fischereiforschung – Information on Fishery research in 2010