title: Proteomic analysis of rare molecular species of translated polypeptides from a mouse fetal thymus cDNA library.
abstract: Proteomic patterns from an ordered cDNA library of mouse fetal thymus origin of an overall complexity of 1536 clones are described. Patterns have been analyzed at 96, 12, or 8 clones in a mixture, or as individual clones. Clones yield in some instances a single spot, in other cases a complex cluster or family of spots is formed. The determination of the clonal address (a six-digit number, indicating the interception of three pooling dimensions) by inspection of pools of 8, 12 or 16 clones is a reliable approach; nevertheless a complete proof consists in retrieving the clone and then submitting to transcription, translation and proteomic analysis. The spot clusters are meaningful clone identifiers; cluster components (families of polypeptides) are characteristic of individual clones and are independent of clones coexisting (and being co-expressed) in a given pool. A 'cluster' originates from a single cloned message and might be due to post-translational modification (offered by the reticuleocyte machinery) or as a result of programmed degradation. Thirteen clones or families of clonal products are shown, and the heterogeneity of the 'appearance' of clones is documented. In about half, the assignment of a clonal polypeptide product to a storage well position has failed; this might be due to a variety of considerations elaborated herein. The arguments are presented, that analysis of abundant proteins of a cell (activated lymphocyte) comprises 'classical proteomics', but for the analysis of the rare molecular species of proteins, Poissonian approaches of replicable material have to be used.
authors.affiliation: Basel Institute for Immunology, Grenzacherstrasse 487, Postfach, CH-4005 Basel, Switzerland. lefkovits@bil.ch
authors.forename: I
authors.initials: I
authors.lastname: Lefkovits
authors.forename: J R
authors.initials: JR
authors.lastname: Kettman
authors.forename: J R
authors.initials: JR
authors.lastname: Frey
mesh_terms: D000818:Animals; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics*; D015180:Electrophoresis, Gel, Two-Dimensional; D005326:Fetal Proteins / Q000235:genetics* / Q000302:isolation & purification; D015723:Gene Library; D051379:Mice; D008807:Mice, Inbred BALB C; D010957:Plasmids / Q000235:genetics; D014176:Protein Biosynthesis; D020543:Proteome / Q000235:genetics* / Q000302:isolation & purification; D012333:RNA, Messenger / Q000235:genetics / Q000302:isolation & purification; D011994:Recombinant Proteins / Q000235:genetics / Q000302:isolation & purification; D013950:Thymus Gland / Q000378:metabolism*
chemical_list: D018076:DNA, Complementary; D005326:Fetal Proteins; D020543:Proteome; D012333:RNA, Messenger; D011994:Recombinant Proteins