Cyclic Nucleotide-Specific Optogenetics Highlights Compartmentalization of the Sperm Flagellum into cAMP Microdomains

Inside the female genital tract, mammalian sperm undergo a maturation process called capacitation, which primes the sperm to navigate across the oviduct and fertilize the egg. Sperm capacitation and motility are controlled by 3′,5′-cyclic adenosine monophosphate (cAMP). Here, we show that optogenetics, the control of cellular signaling by genetically encoded light-activated proteins, allows to manipulate cAMP dynamics in sperm flagella and, thereby, sperm capacitation and motility by light. To this end, we used sperm that express the light-activated phosphodiesterase LAPD or the photo-activated adenylate cyclase bPAC. The control of cAMP by LAPD or bPAC combined with pharmacological interventions provides spatiotemporal precision and allows to probe the physiological function of cAMP compartmentalization in mammalian sperm.

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Thermotaxis of mammalian sperm cells: A potential navigation mechanism in the female genital tract

Nature Medicine ◽

10.1038/nm0203-149 ◽

2003 ◽

Vol 9 (2) ◽

pp. 149-150 ◽

Cited By ~ 148

Author(s):

Anat Bahat ◽

Ilan Tur-Kaspa ◽

Anna Gakamsky ◽

Laura C. Giojalas ◽

Haim Breitbart ◽

...

Keyword(s):

Genital Tract ◽

Female Genital Tract ◽

Sperm Cells ◽

Mammalian Sperm ◽

Female Genital

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Rabbit semen fertility after heterospermic insemination with spermatozoa of different capacitation time

Journal of the Hellenic Veterinary Medical Society ◽

10.12681/jhvms.15766 ◽

2018 ◽

Vol 49 (2) ◽

pp. 143

Author(s):

P. YPSILANTIS (Π. ΥΨΗΛΑΝΤΗΣ) ◽

Ph. SARATSIS (Φ. ΣΑΡΑΤΣΗΣ) ◽

S. SAMOUILIDIS (Σ. ΣΑΜΟΥΗΛΙΔΗΣ)

Keyword(s):

Litter Size ◽

Genital Tract ◽

Female Genital Tract ◽

Group Differences ◽

Sperm Capacitation ◽

Group 4 ◽

Female Genital

The influence of mixing heterogeneous sperm populations in rabbit semen fertility was studied. Eighty female rabbits which were divided in 4 groups (1,2,3 and 4) in = 20.) and 3 males of proven fertility were employed. The animals of group 1,2 and 3 were inseminated with semen from male A j, A2 and A3, respectively, while those of group 4 were inseminated with a mixture containing equal number of progressively motile spermatozoa from each of the above mentioned males ( A 1 + 2 + 3 ) (heterospermic insemination). Animals of each group were divided into 4 subgroups according to the insemination time (15,10, 5 and 0 hours prior the expected ovulation). In each group, differences were observed (P<0.05) between subgroups at the percentage of animals that delivered, indicating differences between males at the time and the duration of sperm capacitation in vivo. Based on the percentage of the animals that delivered and the litter size, semen fertility was improved after the application of heterospermic insemination, at all insemination times. This improvement was attributed to the extension of the time during which capacitated spermatozoa were present in the female genital tract due to the mixture of heterogeneous sperm populations of different capacitation time.

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XIV.—Studies on Reproduction in the Albino Mouse. II. Contributions on the Maturation of the Sperm Cells

Proceedings of the Royal Society of Edinburgh ◽

10.1017/s0370164600012232 ◽

1940 ◽

Vol 59 ◽

pp. 145-152 ◽

Cited By ~ 6

Author(s):

Hugo Merton

Keyword(s):

Genital Tract ◽

Vas Deferens ◽

Female Genital Tract ◽

Morphological Characters ◽

Sperm Cells ◽

Physiological Salt Solution ◽

Mammalian Sperm ◽

Long Time ◽

Slow Passage ◽

Female Genital

The morphological characters of mammalian sperm cells taken from the ductuli efferentes differ only slightly from the sperm derived from the vas deferens. However, it is known that spermatozoa from the caput epididymis, when kept in physiological salt solution, quickly become immotile, whereas those from the cauda epididymis retain their motility for a long time (Moore, 1928). During the slow passage through the epididymis the spermatozoa undergo a physiological process of maturation, which is said to occur under the influence of the epithelium of the epididymis and to result in a lesser susceptibility on the part of the spermatozoa to extraneous influences (Braus and Redenz, 1924; Redenz, 1926; and Lanz, 1929). Other authors maintain that this maturation of the spermatozoon is not conditioned by environmental influences (Young, 1931). In any case the spermatozoa achieve full functional ability only after they have reached the cauda epididymis and the vas deferens. These are the spermatozoa which enter the female genital tract at copulation, and thus it follows that spermatozoa for artificial insemination in the mouse must be taken from the vas deferens and cauda epididymis.

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Membranes of Mammalian Sperm and Capacitation

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010009004x ◽

1976 ◽

Vol 34 ◽

pp. 12-13

Author(s):

M. Gordon

Keyword(s):

Cell Membrane ◽

Outer Membrane ◽

Genital Tract ◽

Acrosome Reaction ◽

Female Genital Tract ◽

Cytochemical Analysis ◽

Mammalian Sperm ◽

Female Genital

Capacitation prepares the mammalian sperm for interaction with the ovum. It occurs in the female genital tract and involves a change in the properties of the membrane over the head. The head membranes are morphologically specialized in different regions. The portion overlying the acrosome is loose and not linked to a cytoplasmic substratum (Fig. 1). It is differentiated from the tight membrane apposed to the post acrosomal cap (PAC) (1). Following capacitation, the periacrosomal segment fuses with the outer membrane of the acrosome allowing escape of the acrosomal contents, the “acrosome reaction”. The fertilizing sperm contacts the vitellus at the PAC. Thus the outer membrane is separated into a portion concerned with the loss of the acrosome and another with ovum contact. The outer membrane of the acrosome is distinguished from the inner since it participates in the acrosome reaction. Cytochemical analysis of the cell membrane supports the concept that the stimulus for capacitation is a change in the properties of the plasmalemma induced by fluids of the female tract.

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