Abstract
Mouse (m) and human embryonic stem cell-derived cardiomyocytes (hESC-CMs) are known to exhibit immature Ca2+ dynamics such as small whole-cell peak amplitude and slower kinetics relative to those of adult. In this study, we examined the maturity and efficiency of Ca2+-induced Ca2+ release in m and hESC-CMs, the presence of transverse (t) tubules and its effects on the regional Ca2+ dynamics. In m and hESC-CMs, fluorescent staining and atomic force microscopy (AFM) were used to detect the presence of t-tubules, caveolin-3, amphiphysin-2 and colocalization of dihydropyridine receptors (DHPRs) and ryanodine receptors (RyRs). To avoid ambiguities, regional electrically-stimulated Ca2+ dynamics of single ESC-CMs, rather than spontaneously beating clusters, were measured using confocal microscopy. m and hESC-CMs showed absence of dyads, with neither t-tubules nor colocalization of DHPRs and RyRs. Caveolin-3 and amphiphysin-2, crucial for the biogenesis of t-tubules with robust expression in adult CMs, were also absent. Single m and hESC-CMs displayed non-uniform Ca2+ dynamics across the cell that is typical of CMs deficient of t-tubules. Local Ca2+ transients exhibited greater peak amplitude at the peripheral than at the central region for m (3.50 ± 0.42 vs. 3.05 ± 0.38) and hESC-CMs (2.96 ± 0.25 vs. 2.72 ± 0.25). Kinetically, both the rates of rise to peak amplitude and transient decay were faster for the peripheral relative to the central region. Immature m and hESC-CMs display unsynchronized Ca2+ transients due to the absence of t-tubules and gene products crucial for their biogenesis. Our results provide insights for driving the maturation of ESC-CMs.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 1493-1500 |
| Number of pages | 8 |
| Journal | Stem Cells and Development |
| Volume | 18 |
| Issue number | 10 |
| DOIs | |
| State | Published - Dec 1 2009 |
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ASJC Scopus subject areas
- Cell Biology
- Developmental Biology
- Hematology
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Absence of transverse tubules contributes to non-uniform Ca2+ wavefronts in mouse and human embryonic stem cell-derived cardiomyocytes. / Lieu, Deborah; Liu, Jing; Siu, Chung Wah; McNerney, Gregory P.; Tse, Hung Fat; Abu-Khalil, Amir; Huser, Thomas R; Li, Ronald A.
In: Stem Cells and Development, Vol. 18, No. 10, 01.12.2009, p. 1493-1500.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Absence of transverse tubules contributes to non-uniform Ca2+ wavefronts in mouse and human embryonic stem cell-derived cardiomyocytes
AU - Lieu, Deborah
AU - Liu, Jing
AU - Siu, Chung Wah
AU - McNerney, Gregory P.
AU - Tse, Hung Fat
AU - Abu-Khalil, Amir
AU - Huser, Thomas R
AU - Li, Ronald A.
PY - 2009/12/1
Y1 - 2009/12/1
N2 - Mouse (m) and human embryonic stem cell-derived cardiomyocytes (hESC-CMs) are known to exhibit immature Ca2+ dynamics such as small whole-cell peak amplitude and slower kinetics relative to those of adult. In this study, we examined the maturity and efficiency of Ca2+-induced Ca2+ release in m and hESC-CMs, the presence of transverse (t) tubules and its effects on the regional Ca2+ dynamics. In m and hESC-CMs, fluorescent staining and atomic force microscopy (AFM) were used to detect the presence of t-tubules, caveolin-3, amphiphysin-2 and colocalization of dihydropyridine receptors (DHPRs) and ryanodine receptors (RyRs). To avoid ambiguities, regional electrically-stimulated Ca2+ dynamics of single ESC-CMs, rather than spontaneously beating clusters, were measured using confocal microscopy. m and hESC-CMs showed absence of dyads, with neither t-tubules nor colocalization of DHPRs and RyRs. Caveolin-3 and amphiphysin-2, crucial for the biogenesis of t-tubules with robust expression in adult CMs, were also absent. Single m and hESC-CMs displayed non-uniform Ca2+ dynamics across the cell that is typical of CMs deficient of t-tubules. Local Ca2+ transients exhibited greater peak amplitude at the peripheral than at the central region for m (3.50 ± 0.42 vs. 3.05 ± 0.38) and hESC-CMs (2.96 ± 0.25 vs. 2.72 ± 0.25). Kinetically, both the rates of rise to peak amplitude and transient decay were faster for the peripheral relative to the central region. Immature m and hESC-CMs display unsynchronized Ca2+ transients due to the absence of t-tubules and gene products crucial for their biogenesis. Our results provide insights for driving the maturation of ESC-CMs.
AB - Mouse (m) and human embryonic stem cell-derived cardiomyocytes (hESC-CMs) are known to exhibit immature Ca2+ dynamics such as small whole-cell peak amplitude and slower kinetics relative to those of adult. In this study, we examined the maturity and efficiency of Ca2+-induced Ca2+ release in m and hESC-CMs, the presence of transverse (t) tubules and its effects on the regional Ca2+ dynamics. In m and hESC-CMs, fluorescent staining and atomic force microscopy (AFM) were used to detect the presence of t-tubules, caveolin-3, amphiphysin-2 and colocalization of dihydropyridine receptors (DHPRs) and ryanodine receptors (RyRs). To avoid ambiguities, regional electrically-stimulated Ca2+ dynamics of single ESC-CMs, rather than spontaneously beating clusters, were measured using confocal microscopy. m and hESC-CMs showed absence of dyads, with neither t-tubules nor colocalization of DHPRs and RyRs. Caveolin-3 and amphiphysin-2, crucial for the biogenesis of t-tubules with robust expression in adult CMs, were also absent. Single m and hESC-CMs displayed non-uniform Ca2+ dynamics across the cell that is typical of CMs deficient of t-tubules. Local Ca2+ transients exhibited greater peak amplitude at the peripheral than at the central region for m (3.50 ± 0.42 vs. 3.05 ± 0.38) and hESC-CMs (2.96 ± 0.25 vs. 2.72 ± 0.25). Kinetically, both the rates of rise to peak amplitude and transient decay were faster for the peripheral relative to the central region. Immature m and hESC-CMs display unsynchronized Ca2+ transients due to the absence of t-tubules and gene products crucial for their biogenesis. Our results provide insights for driving the maturation of ESC-CMs.
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UR - http://www.scopus.com/inward/citedby.url?scp=67650022307&partnerID=8YFLogxK
U2 - 10.1089/scd.2009.0052
DO - 10.1089/scd.2009.0052
M3 - Article
C2 - 19290776
AN - SCOPUS:67650022307
VL - 18
SP - 1493
EP - 1500
JO - Stem Cells and Development
JF - Stem Cells and Development
SN - 1547-3287
IS - 10
ER -