A novel interplay between the ubiquitin-proteasome system and serine proteases during Drosophila development.

Lipinszki, Zoltán and Klement, Éva and Hunyadi-Gulyás, Éva Csilla and Medzihradszky F., Katalin and Márkus, Róbert and Pál, Margit and Deák, Péter and Udvardy, Andor (2013) A novel interplay between the ubiquitin-proteasome system and serine proteases during Drosophila development. BIOCHEMICAL JOURNAL, 454 (3). pp. 571-583. ISSN 0264-6021

[img] Text
Restricted to Repository staff only

Download (2MB) | Request a copy


The concentrations of the Drosophila proteasomal and extraproteasomal polyubiquitin receptors fluctuate in a developmentally regulated fashion. This fluctuation is generated by a previously unidentified proteolytic activity. In the present paper, we describe the purification, identification and characterization of this protease (endoproteinase I). Its expression increases sharply at the L1-L2 larval stages, remains high until the second half of the L3 stage, then declines dramatically. This sharp decrease coincides precisely with the increase of polyubiquitin receptor concentrations in late L3 larvae, which suggests a tight developmental co-regulation. RNAi-induced down-regulation of endoproteinase I results in pupal lethality. Interestingly, we found a cross-talk between the 26S proteasome and this larval protease: transgenic overexpression of the in vivo target of endoproteinase I, the C-terminal half of the proteasomal polyubiquitin receptor subunit p54/Rpn10 results in transcriptional down-regulation of endoproteinase I and consequently a lower level of proteolytic elimination of the polyubiquitin receptors. Another larval protease, Jonah65A-IV, which degrades only unfolded proteins and exhibits similar cross-talk with the proteasome has also been purified and characterized. It may prevent the accumulation of polyubiquitylated proteins in larvae contrary to the low polyubiquitin receptor concentration.

Item Type: Article
Uncontrolled Keywords: Unfolded protein response; *Ubiquitination; Serine Endopeptidases/*chemistry/genetics/*metabolism; RNA, Small Interfering/genetics; PROTEOLYSIS; Proteasome Endopeptidase Complex/*metabolism; Larva/genetics/growth & development/metabolism; Gene Knockdown Techniques; Gene Expression Regulation, Developmental; Enzyme Induction; Drosophila melanogaster/genetics/*growth & development/metabolism; Drosophila Proteins/*chemistry/genetics/*metabolism; Conserved Sequence; Animals; Amino Acid Motifs
Subjects: Q Science / természettudomány > QH Natural history / természetrajz > QH301 Biology / biológia > QH3011 Biochemistry / biokémia
Depositing User: MTMT SWORD
Date Deposited: 10 Jul 2014 13:05
Last Modified: 10 Jul 2014 13:05

Actions (login required)

Edit Item Edit Item