Naslov
Identification of Serum and Plasma Membrane Proteins by use of SELDI-TOF Technique Combined with MS and LC/MS/MS

Autori
D. Josić, M. K. Brown, Y.P. Lim, M. Ručević, H. Callanan, D. C. Hixson.

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Skup
24th International Symphosium on the Separation of Proteins, Peptides and Polynucleotides

Mjesto i datum
Aachen, Njemačka, 19.10.2004. - 22.10.2004

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Nije recenziran

Ključne riječi
Identification; Membrane Proteins; SELDI-TOF; LC/MS/MS Techniques

Sažetak
During malignant transformation, the pattern of the proteins in the cell can be drastically changed. Some of the proteins can also be secreted in serum and other body fluids. Higher concentration of these proteins can indicate the presence of malignant cells and they can be used for diagnostic purposes as tumor markers. Detection, isolation and identification of such potential tumor markers is the first step on the way for rapid and reliable tumor diagnosis. Inter alpha inhibitor proteins (IaIp) are a group proteins, which play an important role in inflammation, wound healing and cancer metastasis. The major forms of these proteins are inter alpha inhibitor (IaI) and pre-alpha inhibitor (PaI) with a molecular weight of 225 kDa and 125 kDa, respectively. The possible use of these proteins as diagnostic and therapeutic agents is under investigation (1). Using 1 and 2-D electrophoresis and SELDI-TOF technique, we isolated an 80 kDa protein, which that was enriched during isolation of IaIp from human plasma. After tryptic digestion and subsequent SELDI-TOF analysis, this protein was identified as inter-alpha-inhibitor heavy chain H3. The presence of this form of IaIp in serum in such high concentration has not been reported previously and its physiological relevance is still unknown. Comparative analysis of nornal rat liver and Morris hepatomas revealed major differences inn protein expression patterns. When several calcium-dependent proteins from Triton-insoluble fraction of plasma membranes, so called rafts, of both liver and Morris hepatoma 7777 were isolated, a protein with an apparent molecular weight in SDS-PAGE of 66-67 kDa was the main component isolated from rat liver. However, in Morris hepatoma 7777, additional calcium dependent proteins with apparent molecular weight between 30 and 40 kDa were also detected. Using SELDI-TOF and ESI-MS these proteins were identified as members of the annexin family. Further characterization of these proteins was performed by use of micro-HPLC and MS/MS after proteolytic digestion. A possible role of annexins in malignant conversion and their use as tumor markers is discussed.

Izvorni jezik
Engleski

Znanstvena područja
Kemija, Biologija, Biotehnologija

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