Organization, ultrastructure, and development of midgut visceral muscle in larval Aedes aegypti

Abstract The midgut muscularis of larvae of the mosquito Aedes aegypti takes the form of a grid of longitudinal and circular muscle bands. The longitudinal and circular bands overlap at near right angles at many areas of intersection. The longitudinal bands run the length of the midgut. However, som...

Full description

Saved in:
Bibliographic Details
Published in:Tissue & cell 2007-08, Vol.39 (4), p.277-292
Main Authors: Bernick, E.P, Moffett, S.B, Moffett, D.F
Format: Article
Language:English
Subjects:
Advanced Basic Science
Aedes - anatomy & histology
Aedes - ultrastructure
Aedes aegypti
Animals
Development
Intestines - ultrastructure
Larva
Larvae
Midgut
Muscle Contraction
Myofibrils - ultrastructure
Sarcomeres - ultrastructure
Species Specificity
Ultrastructure
Visceral muscle
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Abstract The midgut muscularis of larvae of the mosquito Aedes aegypti takes the form of a grid of longitudinal and circular muscle bands. The longitudinal and circular bands overlap at near right angles at many areas of intersection. The longitudinal bands run the length of the midgut. However, some bands of circular muscle, located in the anterior midgut, pass only partway around the gut. An unusual feature was observed at some regions where longitudinal and circular bands of muscle intersect: filaments oriented at near right angles to one another were present in the same membrane-bound fiber. These cruciform regions send contractile elements into both circular and longitudinal bands. The muscularis was fixed in a contracted state, so most of the sarcomeres are represented by complete overlap of myosin and lighter staining actin filaments. Features characteristic of supercontracting muscle, including perforated Z-lines, were seen in sarcomeres of circular muscle bands. Small invaginations resembling transverse tubules were present but a sarcoplasmic reticulum was not observed. While occasional cells that may be neurons or neurosecretory cells were observed, a network that might serve to coordinate the segmentation and peristaltic movement of the muscularis was not apparent.
ISSN:0040-8166
1532-3072
DOI:10.1016/j.tice.2007.05.003