T‐type Ca2+ channels and α1E expression in spermatogenic cells, and their possible relevance to the sperm acrosome reaction

Liévano, Arturo; Santi, Celia M.; Serrano, Carmen; Treviño, Claudia L.; Bellvé, Anthony R.; Hernández‐Cruz, Arturo; Darszon, Alberto

doi:10.1016/0014-5793(96)00515-7

Cited by 160 publications

(174 citation statements)

References 40 publications

Supporting

Mentioning

153

Contrasting

Unclassified

Order By: Relevance

“…Additionally, [Ca 2+ ] i plays a pivotal role in acrosome exocytosis [56][57][58][59][60]. Specific ion channels mediate the rise in [Ca 2+ ] i within sperm, and many candidates for the principle Ca 2+ channel in sperm, including various voltagegated Ca 2+ channels, were proposed based primarily on studies using Ca 2+ imaging, immunolabeling, and patch-clamp experiments from sperm precursors [61][62][63]. However, genetic ablation studies suggested that these candidate proteins were not functionally necessary for male fertility or some compensatory mechanism for their loss may be present [64][65][66][67][68].…”

Section: Calcium Channels and Hyperactivationmentioning

confidence: 99%

Flagellar ion channels of sperm: similarities and differences between species

et al. 2015

View full text Add to dashboard Cite

a b s t r a c tMotility and fertilization potential of mammalian sperm are regulated by ion homeostasis which in turn is under tight control of ion channels and transporters. Sperm intracellular pH, membrane voltage and calcium concentration ([Ca 2+ ] i ) are all important for sperm activity within the female reproductive tract. While all mammalian sperm are united in their goal to find and fertilize an egg, the molecular mechanisms they utilize for this purpose are diverse and differ between species especially on the level of ion channels. Recent direct recording from sperm cells of different species indicate the differences between rodent, non-human primate, ruminant, and human sperm on the basic levels of their ion channel regulation. In this review we summarize the current knowledge about ion channel diversity of the animal kingdom and concentrate our attention on flagellar ion channels of mammalian sperm.

show abstract

Section: Calcium Channels and Hyperactivationmentioning

confidence: 99%

Flagellar ion channels of sperm: similarities and differences between species

et al. 2015

View full text Add to dashboard Cite

show abstract

“…Several voltage-gated calcium channel α1-subunits (i.e. pore-forming) have been identified in sperm (Lievano et al 1996;Westenbroek and Babcock 1999;Wennemuth et al 2000) and calcium channel activity has been found both in late-stage spermatogenic cells and mature sperm (Arnoult et al 1996(Arnoult et al , 1998(Arnoult et al , 1999Benoff 1998;Wennemuth et al 2000). Voltage-gated calcium channels are known to be present on the sperm acrosome, where they are involved in regulating the acrosome reaction (Evans and Florman 2002).…”

Section: Calcium Signallingmentioning

confidence: 99%

Moving to the beat: a review of mammalian sperm motility regulation

Turner¹

2006

Reprod. Fertil. Dev.

240

184

View full text Add to dashboard Cite

Abstract. Because it is generally accepted that a high percentage of poorly motile or immotile sperm will adversely affect male fertility, analysis of sperm motility is a central part of the evaluation of male fertility. In spite of its importance to fertility, poor sperm motility remains only a description of a pathology whose underlying cause is typically poorly understood. The present review is designed to bring the clinician up to date with the most current understanding of the mechanisms that regulate sperm motility and to raise questions about how aberrations in these mechanisms could be the underlying causes of this pathology.

show abstract

“…Probing of a germ line cell library for mRNA of Ca 2ϩ channel ␣ 1 subunits found predominant message for ␣ 1E (4). Whole cell recording from spermatocytes and spermatids found only transient, low voltage-activated (LVA) 1 Ca 2ϩ currents (5)(6)(7)(8).…”

mentioning

confidence: 99%

CaV2.2 and CaV2.3 (N- and R-type) Ca2+ Channels in Depolarization-evoked Entry of Ca2+ into Mouse Sperm

Wennemuth

Westenbroek

et al. 2000

Journal of Biological Chemistry

158

160

View full text Add to dashboard Cite

2؉ channels in epididymal sperm examined prior to capacitation. Involvement of a previously undetected Ca V 2.2 (N-type) channel, suggested by the action of GVIA, is substantiated by immunodetection of Ca 2؉ channel ␣ 1B subunits in sperm and sperm extracts. Resistance to dihydropyridines, calciseptine, MVIIC, and kurtoxin indicates that Ca V 1, Ca V 2.1, and Ca V 3 (L-, P/Q-, and T-type) channels contribute little to this evoked response. Partial sensitivity to 1 M mibefradil and an enhanced sensitivity of the GVIAresistant component of response to Ni 2؉ suggest participation of a Ca V 2.3 (R-type) channel specified by previously found ␣ 1E subunits. Our examination of depolarizationevoked Ca 2؉ entry indicates that mature sperm possess a larger palette of voltage-gated Ca 2؉ channels than previously thought. Such diversity may permit specific responses to multiple cues encountered on the path to fertilization.Identification and characterization of sperm Ca 2ϩ entry channels and the mechanisms that modulate their function as sperm prepare to fertilize an egg remain major unsolved problems in reproductive biology (1-3). These challenges stand unmet largely because of the difficulty of applying patch-clamp methods and the tools of molecular biology to sperm. The poorly understood nature of the modifications to sperm that occur between mating and fertilization ("capacitation") presents an additional barrier to investigation.Several indirect approaches have been informative. Probing of a germ line cell library for mRNA of Ca 2ϩ channel ␣ 1 subunits found predominant message for ␣ 1E (4). Whole cell recording from spermatocytes and spermatids found only transient, low voltage-activated (LVA) 1 Ca 2ϩ currents (5-8). Finally, pharmacological sensitivities for spermatid Ca 2ϩ currents showed some parallels with those for Ca 2ϩ -mediated responses of sperm (8, 9). On the basis of these results, it was proposed that a T-type Ca 2ϩ channel is specified by ␣ 1E and is retained after spermiogenesis to provide the major route for depolarization-evoked entry of Ca 2ϩ into sperm. Newer work has shown that expression of ␣ 1E produces Rtype rather than T-type channels (10) and has increased the number of Ca 2ϩ channels found in the germ line. Message for the ␣ 1G and ␣ 1H subunits, now known to specify T-type channels (11-17), has been found in spermatogenic cells (18). Study by immunological methods showed that sperm contain ␣ 1E , ␣ 1A , and ␣ 1C channel proteins (19). If these proteins are functionally active, then P/Q-and L-type channels also might provide routes for entry of Ca 2ϩ (see Table I). Here, we use the kinetics of depolarization-evoked increases in the intracellular free [Ca 2ϩ ] (Ca i ) of epididymal sperm to monitor the activity of voltage-gated Ca 2ϩ channels and examine their pharmacological sensitivity. The results indicate that a portion of the observed activity requires opening of N-type Ca 2ϩ channels, specified by ␣ 1B Ca 2ϩ channel proteins that are detected here for the first time in sperm and sperm e...

show abstract

T‐type Ca²⁺ channels and α_1E expression in spermatogenic cells, and their possible relevance to the sperm acrosome reaction

Cited by 160 publications

References 40 publications

Flagellar ion channels of sperm: similarities and differences between species

Flagellar ion channels of sperm: similarities and differences between species

Moving to the beat: a review of mammalian sperm motility regulation

CaV2.2 and CaV2.3 (N- and R-type) Ca2+ Channels in Depolarization-evoked Entry of Ca2+ into Mouse Sperm

Contact Info

Product

Resources

About