Investigation of cell movement and the associated cytoskeleton during chick gastrulation and somitogenesis

Cell migration involves dynamic and spatially regulated changes to the cytoskeleton. During avian gastrulation, cells ingress through the primitive streak. Previous characterisation of microtubule organisation during this process revealed the distribution of cells with polarised and radial arrays across different regions of the embryo. Interestingly, many cells organised into groups arranged in rosette-like structures. As the primitive streak regresses and the neural folds gather at the centre of the embryo, bands of paraxial mesoderm that lie either side of the neural tube separate into somites. As new somites form caudally, the more rostral somites undergo a process of morphogenesis. Each somite divides into two regions: the dermomyotome and the sclerotome. Little is known about the cytoskeletonduring this process. Signalling by the Wnt family of secreted proteins influences the fate of cells during early embryonic patterning, cell movement, and cell polarity, processes in which the cytoskeleton is noticeably modified. The microtubule and actin crosslinking factor-1/actin crosslinking factor-7 (MACF1/ACF7) protein has been implicated in Wnt signalling and, additionally, its regulation has been shown to be important in cell migration. This thesis concentrates on cellular dynamics and organisation (and the associated cytoskeleton) during chick gastrulation and somitogenesis. The aims of this project were to a) further characterise the cytoskeleton in cells that ingress into the avian primitive streak. b) Establish a published electroporation technique, which permits the targeting of different regions of the somite and subsequently observe cells (and their associated cytoskeleton) in real time. c) Determine the expression pattern for MACF1/ACF7 in chick. d) To ascertain if there is a direct role for canonical Wnt signalling in somitic myofibre orientation/organisation.

Name dc:type.qualificationname

phd

Level dc:type.qualificationlevel

doctoral

Grantor dc:publisher.institution

University of East Anglia

Year dc:date.issued

2013

Author dc:creator

• Kennerley, Nicola

Language dc:language

en