Cytoskeleton Dynamics Powers Nematode Sperm Motility

1973 ◽

Vol 31 ◽

pp. 626-627

Author(s):

Ezzatollah Keyhani ◽

Larry F. Lemanski ◽

Sharon L. Lemanski

Keyword(s):

Plasma Membrane ◽

Sperm Motility ◽

Substrate Oxidation ◽

Ambystoma Mexicanum ◽

Axial Filament ◽

Mexican Axolotl ◽

Middle Piece

Energy for sperm motility is provided by both glycolytic and respiratory pathways. Mitochondria are involved in the latter pathway and conserve energy of substrate oxidation by coupling to phosphorylation. During spermatogenesis, the mitochondria undergo extensive transformation which in many species leads to the formation of a nebemkem. The nebemkem subsequently forms into a helix around the axial filament complex in the middle piece of spermatozoa.Immature spermatozoa of axolotls contain numerous small spherical mitochondria which are randomly distributed throughout the cytoplasm (Fig. 1). As maturation progresses, the mitochondria appear to migrate to the middle piece region where they become tightly packed to form a crystalline-like sheath. The cytoplasm in this region is no longer abundant (Fig. 2) and the plasma membrane is now closely apposed to the outside of the mitochondrial layer.

Download Full-text

Spatial control of actin-based motility through plasmalemmal PtdIns(4,5)P2-rich raft assemblies.

Biochemical Society Symposium ◽

10.1042/bss0720119 ◽

2005 ◽

Vol 72 ◽

pp. 119-127 ◽

Cited By ~ 19

Author(s):

Tamara Golub ◽

Caroni Pico

Keyword(s):

Protein Kinase ◽

Cell Surface ◽

Actin Cytoskeleton ◽

Lipid Rafts ◽

Patch Clustering ◽

Pkc Protein Kinase C ◽

Membrane Bound ◽

And Function ◽

Cytoskeleton Dynamics ◽

Syndrome Protein

The interactions of cells with their environment involve regulated actin-based motility at defined positions along the cell surface. Sphingolipid- and cholesterol-dependent microdomains (rafts) order proteins at biological membranes, and have been implicated in most signalling processes at the cell surface. Many membrane-bound components that regulate actin cytoskeleton dynamics and cell-surface motility associate with PtdIns(4,5)P2-rich lipid rafts. Although raft integrity is not required for substrate-directed cell spreading, or to initiate signalling for motility, it is a prerequisite for sustained and organized motility. Plasmalemmal rafts redistribute rapidly in response to signals, triggering motility. This process involves the removal of rafts from sites that are not interacting with the substrate, apparently through endocytosis, and a local accumulation at sites of integrin-mediated substrate interactions. PtdIns(4,5)P2-rich lipid rafts can assemble into patches in a process depending on PtdIns(4,5)P2, Cdc42 (cell-division control 42), N-WASP (neural Wiskott-Aldrich syndrome protein) and actin cytoskeleton dynamics. The raft patches are sites of signal-induced actin assembly, and their accumulation locally promotes sustained motility. The patches capture microtubules, which promote patch clustering through PKA (protein kinase A), to steer motility. Raft accumulation at the cell surface, and its coupling to motility are influenced greatly by the expression of intrinsic raft-associated components that associate with the cytosolic leaflet of lipid rafts. Among them, GAP43 (growth-associated protein 43)-like proteins interact with PtdIns(4,5)P2 in a Ca2+/calmodulin and PKC (protein kinase C)-regulated manner, and function as intrinsic determinants of motility and anatomical plasticity. Plasmalemmal PtdIns(4,5)P2-rich raft assemblies thus provide powerful organizational principles for tight spatial and temporal control of signalling in motility.

Download Full-text

Interactive effects of ocean warming and acidification on sperm motility and fertilization in the mussel Mytilus galloprovincialis

Marine Ecology Progress Series ◽

10.3354/meps11944 ◽

2016 ◽

Vol 562 ◽

pp. 101-111 ◽

Cited By ~ 12

Author(s):

AR Eads ◽

WJ Kennington ◽

JP Evans

Keyword(s):

Sperm Motility ◽

Mytilus Galloprovincialis ◽

Ocean Warming ◽

Interactive Effects

Download Full-text

Kriopreservasi Semen Kambing Boer dengan Konsentrasi Pengencer Nira Aren dan Gliserol Berbeda

Jurnal Ilmu dan Teknologi Peternakan Tropis ◽

10.33772/jitro.v6i1.5422 ◽

2019 ◽

Vol 6 (1) ◽

pp. 1

Author(s):

Muhammad Riyadhi ◽

Anis Wahdi ◽

Muhammad Rizal

Keyword(s):

Sperm Motility ◽

Membrane Integrity ◽

Egg Yolk ◽

Boer Goat ◽

Palm Juice ◽

Sperm Membrane ◽

Live Sperm

ABSTRAK Penelitian bertujuan untuk mengetahui efektivitas nira aren sebagai pengencer alternatif dalam proses pembekuan (kriopreservasi) semen kambing boer.Kriopreservasi semen kambing boer menggunakan pengencer tris-gliserol-kuning telur (P1 73-7-20%), nira aren-gliseol-kuning telur(masing-masing P2 74-6-20%, P3 73-7-20%, dan P4 72-8-20%) dan andromed (P5 tanpa mengandung kuning telur dan gliserol). Parameter evaluasi meliputi motilitas, viabilitas, dan membrane plasma utuh setelah pengenceran, ekuilibrasi dan thawing. Evaluasi motilitas pasca thawing menunjukkan P5 52% berbeda nyata (P<0.05) dengan P1 42%, selanjutnya P5 dan P1 berbeda sangat nyata (P<0.05) dengan P2 8%, P3 6% dan P4 12%. Viabilitas pasca thawing menunjukkan P5 65,4% tidak berbeda nyata (P>0,05) dengan P1 61,8%, akan tetapi P5 dan P1 berbeda sangat nyata (P<0.05) dengan P2 26,2%, P3 29,8%, dan P4 34%. Membran plasma utuh (MPU) pasca thawing menunjukkan P5 66,2% tidak berbeda nyata (P>0,05) dengan P1 65,4%, akan tetapi keduanya berbeda sangat nyata (P<0.05) dengan P2 39%, P3 38%, dan P4 36,2%. Disimpulkan kriopreservasi semen kambing boer dengan pengencer nira aren dan gliserol pada konsentrasi berbeda belum dapat dipergunakan sebagai sumber bibit berdasarkan standar nasional Indonesia.Kata Kunci : Kambing boer, semen, nira arenABSTRACTThe experiment was conducted to determine the effect of sugar palm juice as alternative extender for cryopreservation process of boer semen.Tris-glycerol-egg yolk (P1 73-7-20%), Sugar palm juice-glyserol-egg yolk (P2 74-6-20%, P373-7-20%, dan P4 72-8-20%), and andromed (P5) used as a extender in the cryopreservation process of boer semen. Sperm motility (%), live sperm (%) and sperm membrane integrity (%) were recorded after diluted, equilibration and freeze-thawing. Result of post thawing motility showed that P5 52% was significantly different (P <0.05) with P1 42%, then P5 and P1 were significantly different (P <0.05) with P2 8%, P3 6% and P4 12%. Viability after thawing showed P5 65.4% was not significantly different (P> 0.05) with P1 61.8%, but P5 and P1 significantly different (P <0.05) with P2 26.2%, P3 29.8 %, and P4 34%. Spermmembrane integrity post-thawing showed P5 66.2% was not significantly different (P> 0.05) with P1 65.4%, but both were very significantly different (P <0.05) with P2 39%, P3 38% and P4 36.2%. Conclusions, sugar palm juice-glycerol-egg yolk with differentconcentrationsineffectively as an alternative extenderin cryopreservation of boer semen.Keywords: boer goat, semen, sugar palm juice

Download Full-text