title: Ubiquitin-proteasome system components are upregulated during intestinal regeneration.
abstract: The ubiquitin proteasome system (UPS) is the main proteolytic system of cells. Recent evidence suggests that the UPS plays a regulatory role in regeneration processes. Here, we explore the possibility that the UPS is involved during intestinal regeneration of the sea cucumber Holothuria glaberrima. These organisms can regenerate most of their digestive tract following a process of evisceration. Initially, we identified components of H. glaberrima UPS, including sequences for Rpn10, β3, and ubiquitin-RPL40. Predicted proteins from the mRNA sequences showed high degree of conservation that ranged from 60% (Rpn10) to 98% (Ub-RPL40). Microarrays and RT-PCR experiments showed that these genes were upregulated during intestinal regeneration. In addition, we demonstrated expression of alpha 20S proteasome subunits and ubiquitinated proteins during intestinal regeneration and detected them in the epithelium and connective tissue of the regenerating intestine. Finally, the intestinal regeneration was altered in animals treated with MG132, a proteasome inhibitor. These findings support our contention that proteasomes are playing an important role during intestinal regeneration.
authors.affiliation: Department of Biology, University of Puerto Rico, Rio Piedras Campus, San Juan, Puerto Rico 00931.
authors.forename: Consuelo
authors.initials: C
authors.lastname: Pasten
authors.forename: Pablo A
authors.initials: PA
authors.lastname: Ortiz-Pineda
authors.forename: José E
authors.initials: JE
authors.lastname: García-Arrarás
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D004848:Epithelium / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D007150:Immunohistochemistry; D007422:Intestines / Q000196:embryology / Q000502:physiology*; D008969:Molecular Sequence Data; D020411:Oligonucleotide Array Sequence Analysis; D038081:Organogenesis; D046988:Proteasome Endopeptidase Complex / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012038:Regeneration; D012616:Sea Cucumbers / Q000235:genetics / Q000378:metabolism; D025801:Ubiquitin / Q000235:genetics / Q000378:metabolism*; D015854:Up-Regulation
chemical_list: D012333:RNA, Messenger; D025801:Ubiquitin; D046988:Proteasome Endopeptidase Complex