Volume 2 • Issue 1 • 1000105
Altern Integ Med
ISSN: AIM, an open access journal
Open Access Research Article
Alternative and Integrative Medicine
Spera et al., Altern Integ Med 2013, 2:1
http://dx.doi.org/10.4172/aim.1000105
Keywords:
1
H–NMR; Mass spectrometry; CHO–K1; cAMP; Cell
cycle
Abbreviation
Magnetic Resonance; MS=Mass Spectrometry; cAMP=Adenosine 3’,5’
Cyclic Monophosphate; RT= Reverse Transformation; Myh10=myosin,
Heavy Chain 10, Non-Muscle; Gna11=Guanine Nucleotide Binding
Protein, Alpha 11; S61A1=Sec61 Alpha 1 Subunit; CD82=Cluster
of Diferentiation 82; FCS=Fetal Calf Serum; TSP=Trimethylsilyl
Propionate; ppm=Part Per Million; HPLC=High Performance Liquid
Chromatography; MALDI TOF=Matrix Assisted Laser Desorption
Ionization Time of Flight; HCCA=α-Cyano-4-Hydroxycinnamic
Acid; TFA=Trifuoroacetic Acid; PMSF=Phenylmethanesulfonyl
Fluoride; DTT= Dithiothreitol; rpm=Revolutions per minute;
G6PD=Glucose-6-Phosphate Dehydrogenase; NADP+=Nicotinamide
Adenine Dinucleotide Phosphate; NAD+=Nicotinamide Adenine
Dinucleotide; LDH= Lactate Dehydrogenase; S.D.=Standard Deviation;
nmMHC=Nonmuscle Myosin Heavy Chain; nmMHC-A=Nonmuscle
Myosin Heavy Chain A; nmMHC-B=Nonmuscle Myosin Heavy Chain
B; ATP=Adenosine 5’-Triposphate.
Introduction
Chinese hamster ovary fbroblasts (CHO–K1) cells are a good
model to study the transformation of microtubules and nuclear DNA
during cell cycle. Te standard CHO-K1 cell displays the classical
stigmata of malignantly transformed cells grown in vitro [1]; it has been
reported that adenosine 3’,5’ cyclic monophosphate (cAMP) causes
cell diferentiation [2] and in particular it causes CHO-K1 cells to lose
these transformation characteristics and to assume the morphological
habitus approaching that of normal fbroblasts. Tis process is named
“reverse transformation” (RT) [3].
It was found that untreated and cAMP treated cells difer only
in terms of the three-dimensional organisation and orientation
of microtubules and are quite similar in terms of the amount of
polymerised tubulin [3-7]. Microtubules and chromatin-DNA structure
have impact on various biological processes such as the control of gene
expression, the protein synthesis, the cell cycle regulation and the cell
transformation [8-11]. Transformed cells frequently exhibit instability
in chromosome number even in clonal populations. Defects in the
cytoskeletal structure could well be refected in corresponding defects
in the spindle, which is made of microtubules and which would result
in errors of chromosomal distribution among the cell progeny.
However, the changes in the concentration of the diferent
metabolites and the diferent protein composition associated with
morphological changes observed are largely unknown [4]. Puck et al.
proposed that the cytoskeleton transmits information from the cell
membrane to chromosomal loci in the nucleus and is an important
element in regulation of the exposure process [12,13]. Te mechanism
of the transformation in properties here described is as yet obscure. Te
phenomena make clear that a fundamental change in properties of the
cell membrane has occurred.
We had analyzed the CHO-K1 cell protein composition, in
particular of the nuclear compartment, by mass spectrometry (MS) to
identify changing in the protein pattern before and afer the reverse
transformation [14]. We identifed three proteins, Myh10, Gna11 and
S61A1 present in the nucleus of untreated cells and absent afer cAMP
exposure. Moreover we identifed another protein, Cd82Mouse, which
concentration is halved afer the diferentiation.
We choose
1
H-NMR since it is revealed an extremely useful and a
noninvasive technique in monitoring cell metabolism [15–18]. Since it
is known that CHO–K1 cells show diferent growth features depending
on the growth medium, we frst studied the variation in CHO–K1
metabolism with the addition of 10% fetal calf serum (FCS), observing
*Corresponding author: Claudio Nicolini, President Nanoworld Institute
Fondazione EL.B.A.Nicolini, Largo Redaelli 7, Pradalunga, Bergamo, Italy, E-mail:
claudio.nicolini@unige.it
Received February 03, 2013; Accepted March 04, 2013; Published March 07,
2013
Citation: Spera R, Vasile F, Pechkova E, Nicolini C (2013) Correlation of
Changes of Cho–K1 Cells Metabolism to Changes in Protein Expression in Camp
Differentiation. Altern Integ Med 2: 105. doi:10.4172/aim.1000105
Copyright: © 2013 Spera R, et al. This is an open-access article distributed under
the terms of the Creative Commons Attribution License, which permits unrestricted
use, distribution, and reproduction in any medium, provided the original author and
source are credited.
Correlation of Changes of Cho–K1 Cells Metabolism to Changes in Protein
Expression in Camp Differentiation
Spera R, Vasile F, Pechkova E and Nicolini C*
Nanoworld Institute , Fondazione EL.B.A.Nicolini, Pradalunga, Bergamo, and Laboratory of Nanobiotechnology and Biophysics, Genoa University, Genova, Italy
Abstract
A correlated investigation of cell metabolism and protein expression of Chinese Hamster Ovary cells (CHO-K1)
under different growth conditions was performed by
1
H nuclear magnetic resonance (
1
H-NMR), mass spectrometry
(MS) and biochemical assays. CHO fbroblasts have shown different metabolic products when grown in different
media and when differentiation is stimulated by adenosine 3’, 5’ cyclic monophosphate (cAMP). In particular, while
addition of Fetal Calf Serum causes an increase in the glucose metabolism correlated to changes in lipid composition
of the membrane observed by
1
H-NMR, differentiation induced by cAMP causes biochemical differences in glucose
and lipidic metabolism uniquely correlated both to the specifc changes in the composition of nuclear proteins,
revealed by mass spectrometry, and to the differences in metabolism, determined by NMR.
CHO-K1=Chinese Hamster Ovary cells;
1
H-NMR=
1
H Nuclear
Te goal of this paper is to investigate the correlations between
changing in the cellular metabolism and in the cellular protein
expression afer RT, in order to obtain more information on this cellular
process. To this aim we coupled two powerful techniques: nuclear
magnetic resonance (
1
H-NMR) and MS. We think that this approach
could be of wide application in the study of many cellular systems.