title: Molecular identification and functional characterisation of uncoupling protein 4 in larva and pupa fat body mitochondria from the beetle Zophobas atratus.
abstract: Uncoupling protein 4 (UCP4) is a member of the UCP subfamily that mediates mitochondrial uncoupling, and sequence alignment predicts the existence of UCP4 in several insects. The present study demonstrates the first molecular identification of a partial Zophobas atratus UCP4-coding sequence and the functional characterisation of ZaUCP4 in the mitochondria of larval and pupal fat bodies of the beetle. ZaUCP4 shows a high similarity to predicted insect UCP4 isoforms and known mammalian UCP4s, both at the nucleotide and amino acid sequence levels. Bioenergetic studies clearly demonstrate UCP function in mitochondria from larval and pupal fat bodies. In non-phosphorylating mitochondria, ZaUCP activity was stimulated by palmitic acid and inhibited by the purine nucleotide GTP. In phosphorylating mitochondria, ZaUCP4 activity decreased the yield of oxidative phosphorylation. ZaUCP4 was immunodetected with antibodies raised against human UCP4 as a single 36-kDa band. A lower expression of ZaUCP4 at the level of mRNA and protein and a decreased ZaUCP4 activity were observed in the Z. atratus pupal fat body compared with the larval fat body. The different expression patterns and activity of ZaUCP4 during the larval-pupal transformation indicates an important physiological role for UCP4 in insect fat body development and function during insect metamorphosis.
authors.affiliation: Department of Animal Physiology and Development, Umultowska 89, 61-614 Poznan, Poland. slocina@amu.edu.pl
authors.forename: Malgorzata
authors.initials: M
authors.lastname: Slocinska
authors.forename: Nina
authors.initials: N
authors.lastname: Antos-Krzeminska
authors.forename: Grzegorz
authors.initials: G
authors.lastname: Rosinski
authors.forename: Wieslawa
authors.initials: W
authors.lastname: Jarmuszkiewicz
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D001517:Coleoptera / Q000235:genetics / Q000378:metabolism*; D017124:Conserved Sequence; D020536:Enzyme Activators / Q000494:pharmacology; D005216:Fat Body / Q000378:metabolism*; D015870:Gene Expression; D018507:Gene Expression Regulation, Developmental; D019476:Insect Proteins / Q000235:genetics* / Q000378:metabolism; D007814:Larva / Q000378:metabolism; D026901:Membrane Transport Proteins / Q000235:genetics* / Q000378:metabolism; D008928:Mitochondria / Q000378:metabolism*; D008969:Molecular Sequence Data; D010101:Oxygen Consumption; D019308:Palmitic Acid / Q000494:pharmacology; D011679:Pupa / Q000378:metabolism; D017422:Sequence Analysis, DNA
chemical_list: D020536:Enzyme Activators; D019476:Insect Proteins; D026901:Membrane Transport Proteins; D019308:Palmitic Acid