title: Hemoglobin system of Sparus aurata: changes in fishes farmed under extreme conditions.
abstract: In order to gain more knowledge on the stress responses of gilhead seabream (Sparus aurata) under extreme conditions, this study investigated the functional properties of the hemoglobin system and globin gene expression under hypoxia and low salinity. The oxygen affinity for the two hemoglobin components present inside the S. aurata erythrocyte was practically identical as was the influence of protons and organic phosphates (Root effect). The quantification of S. aurata hemoglobin fractions performed by HPLC and the data on gene expression of globin chains assayed by PCR indicate that under hypoxia and low salinity there is a change in the ratio between the two different hemoglobin components. The result indicating that the distinct hemoglobins present in S. aurata erythrocyte have almost identical functional properties, does not explain the adaptive response (expression change) following exposure of the animal to hypoxia or low salinity on the basis of their function as oxygen transporter. We hypothesize that other parallel biological functions that the hemoglobin molecule is known to display within the erythrocyte are involved in adaptive molecular mechanisms. The autoxidation-reduction cycle of hemoglobin could be involved in the response to particular living conditions.
authors.affiliation: Department of Biochemical, Physiological and Nutritional Sciences, School of Medicine, University of Messina, Policlinico Universitario, Torre Biologica, 5 degrees piano, Via C. Valeria, 98125 Messina, Italy.
authors.forename: Salvatore
authors.initials: S
authors.lastname: Campo
authors.forename: Giancarlo
authors.initials: G
authors.lastname: Nastasi
authors.forename: Angela
authors.initials: A
authors.lastname: D'Ascola
authors.forename: Giuseppe M
authors.initials: GM
authors.lastname: Campo
authors.forename: Angela
authors.initials: A
authors.lastname: Avenoso
authors.forename: Paola
authors.initials: P
authors.lastname: Traina
authors.forename: Alberto
authors.initials: A
authors.lastname: Calatroni
authors.forename: Emanuele
authors.initials: E
authors.lastname: Burrascano
authors.forename: Alida
authors.initials: A
authors.lastname: Ferlazzo
authors.forename: Giulio
authors.initials: G
authors.lastname: Lupidi
authors.forename: Rosita
authors.initials: R
authors.lastname: Gabbianelli
authors.forename: Giancarlo
authors.initials: G
authors.lastname: Falcioni
mesh_terms: D000818:Animals; D017756:Aquaculture; D002851:Chromatography, High Pressure Liquid; D004912:Erythrocytes / Q000737:chemistry / Q000378:metabolism; D015870:Gene Expression; D005914:Globins / Q000235:genetics / Q000378:metabolism; D006454:Hemoglobins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D000860:Hypoxia / Q000097:blood* / Q000235:genetics; D010100:Oxygen / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D054712:Salinity; D021541:Sea Bream / Q000097:blood* / Q000235:genetics
chemical_list: D006454:Hemoglobins; D012333:RNA, Messenger; D005914:Globins; D010100:Oxygen