Evolutionary Dynamics of the Alpha-actinin Gene Family

The alpha-actinin gene family is a member of the spectrin superfamily of proteins. Other members of this superfamily include the a- and ~-spectrins, ~heavy spectrin and dystrophin. Each member of this superfamily has a unique actin cross-linking distance consequent to the specific number of spectrin repeats within the central repeat region of the superfamily. Alpha-actinin is thought to be the least derived of the spectrin superfamily due to its possession of the smallest number of spectrin repeats. Though many a-actinins are known, the relationships among them are as yet undetermined. I performed phylogenetic analyses on a-actinin sequences to establish the kinship among a-actinin isoforms and to taxonomically treat the sequences. In addition, I sequenced and analyzed a previously unknown rat a-actinin 3. Analyses support four main isoforms of a-actinin. I also investigated homogenizing evolution within the spectrin repeats of the gene family. This was accomplished using gene conversion analyses and a new analysis which implements a continuum of the two known modes of homogenizing evolution: birth-and-death evolution and concerted evolution. This conceptual leap to a continuous model has not previously been made. Furthering these generalized studies of the a-actinin gene family, I used RT-PCR, cloning and automated DNA sequencing to obtain 77bp of sequence for what may be yet another member of the spectrin superfamily, the G3.5 antigen.

Name thesis:degree_name

Master of Science

Level thesis:degree_level

Masters

Discipline thesis:degree_discipline

Geography

Grantor

Southwest Texas State University

Year dc:date.issued

2001

Author dc:creator

• Dixson, Jamie D.

Advisor dc:contributor.advisor

• Garcia, Dana M.

Committee members dc:contributor.committeemember

• Forstner, Michael R. J.
• Koke, Joseph R.

• actin genes
• spectrin

Language dc:language.iso

en

Handle dc:identifier.uri

https://hdl.handle.net/10877/9739

OAI identifier oai:identifier

oai:digital.library.txst.edu:10877/9739