Naked Science Forum

Life Sciences => Physiology & Medicine => Topic started by: Rokitansky on 08/06/2004 15:43:20

Title: Smooth muscle-tropomyosin
Post by: Rokitansky on 08/06/2004 15:43:20

Do we know something about a role of tropomyosin in SMOOTH muscle cells ???

Title: Re: Smooth muscle-tropomyosin
Post by: cuso4 on 10/06/2004 11:55:35

Is tropomyosin the molecule that is around actin filament?

I seem to remember that during muscle contraction, Ca2+ ions attaches to the tropomyosin exposing the myosin binding site on the actin molecule. This enable myosin to bind with actin filament and allow cross bridge cycle (rachet mechanism) to take place.

I've done this in school, but I remember it only vaguely so I could be wrong.

Angel

Title: Re: Smooth muscle-tropomyosin
Post by: Rokitansky on 10/06/2004 14:39:07

No, Ca++ attaches to troponin C, only in striated muscle.
Smooth muscles lack Troponin. But thay have tropomyiosin. But what does it work ?

Title: Re: Smooth muscle-tropomyosin
Post by: DrN on 12/06/2004 21:28:53

Hi, i think it has something to do with vascular stretch, presumably a response for vasoconstriction/dilation? not sure beyond that.