Purification and cDNA cloning of ferritin from the hepatopancreas of the freshwater crayfish Pacifastacus leniusculus.
Ferritin was purified from the hepatopancreas of the freshwater crayfish Pacifastacus leniusculus after injection of iron. It has the same size as horse spleen ferritin (440 kDa) and migrates as two bands, 19 kDa and 20 kDa, respectively, in SDS/PAGE under reducing conditions. Crayfish ferritin (20 kDa) was cloned from a hepatopancreas cDNA library. The deduced amino acid sequence of the crayfish ferritin shows a closer relationship to vertebrate ferritin heavy chains than to insect ferritin and contains the conserved H-specific residues for the ferroxidase centre found in vertebrate ferritin heavy chain. An IRE(iron-responsive element)-like sequence with a predicted stem-loop structure was present in the 5' untranslated region of the crayfish ferritin mRNA. Crayfish ferritin does not share the atypical properties of insect ferritins, such as high molecular mass of intact protein, abundance in hemolymph, and export into vacuoles. We suggest that there are two different types of ferritins distributed in different species: insect-type or secretory ferritins which are predominant in the snail oocyte and insects, and vertebrate (crustacean)-type or cytosolic ferritins which are predominant in vertebrates and crustacea.
Huang
T S
TS
Department of Physiological Botany, University of Uppsala, Sweden.
Law
J H
JH
Söderhäll
K
K
D000818:Animals; D003400:Astacoidea / Q000235:genetics*; D001483:Base Sequence; D003001:Cloning, Molecular; D017931:DNA Primers / Q000737:chemistry; D018076:DNA, Complementary / Q000235:genetics; D005293:Ferritins / Q000235:genetics*; D015870:Gene Expression; D008099:Liver / Q000737:chemistry; D008969:Molecular Sequence Data; D010179:Pancreas / Q000737:chemistry; D010802:Phylogeny; D012333:RNA, Messenger / Q000235:genetics; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid
D017931:DNA Primers; D018076:DNA, Complementary; D012333:RNA, Messenger; D005293:Ferritins