Ultrastructural and biochemical analysis of sperm flagella from an infertile man with a rod-dominant retinal degeneration.
This study examined the ultrastructural morphology and posttranslationally modified alpha-tubulin isoforms in the sperm flagella of a patient presenting with infertility and retinal degeneration. Clinical evaluation showed impaired motility and gross morphological abnormalities of the sperm and a rod-dominant retinal degeneration with midperipheral pigment clumping and scattered bone spicules. Other neurological indications included delayed neuroelectric transmission in the auditory brainstem and a temporal lobe seizure disorder. Ultrastructural analysis showed that 46% of sperm axonemes had missing and/or misplaced doublets compared with 10% to 12% in control subjects. ELISA analysis showed hypoacetylation of alpha-tubulin (30% of control) but normal levels of alpha-tubulin tyrosination. Tubulin acetyl-transferase specific activity was also 30% of control activity. These characteristics may be indicative of microtubule instability leading to the pathological consequences described.
Laboratory of Retinal Cell and Molecular Biology, National Eye Institute, National Institutes of Health, Bethesda, MD 20892-2740, USA.
S
S
Gentleman
M I
MI
Kaiser-Kupfer
R J
RJ
Sherins
R
R
Caruso
W G
WG
Robison
R A
RA
Lloyd-Muhammad
M A
MA
Crawford
A
A
Pikus
G J
GJ
Chader
D000123:Acetyltransferases / Q000378:metabolism; D000328:Adult; D016057:Evoked Potentials, Auditory, Brain Stem; D006311:Hearing Disorders / Q000150:complications; D006801:Humans; D007248:Infertility, Male / Q000150:complications* / Q000378:metabolism*; D008297:Male; D012162:Retinal Degeneration / Q000150:complications* / Q000378:metabolism*; D013094:Spermatozoa / Q000737:chemistry / Q000648:ultrastructure; D014404:Tubulin / Q000378:metabolism
D014404:Tubulin; D000123:Acetyltransferases