The expression patterns of beta1,4 galactosyltransferase I and V mRNAs, and Galbeta1-4GlcNAc group in rat gastrocnemius muscles post sciatic nerve injury.
Glycosylation is one of the most important post-translational modifications. It is clear that the single step of beta1,4-galactosylation is performed by a family of beta1,4-galactosyltransferases (beta1,4-GalTs), and that each member of this family may play a distinct role in different tissues and cells. beta1,4-GalT I and V are involved in the biosynthesis of N-linked oligosaccharides and play roles in sciatic nerve regeneration after sciatic nerve injury. In the present study, the expression of beta1,4-galactosyltransferase (beta1,4-GalT) I, V mRNAs and Galbeta1-4GlcNAc group were examined in rat gastrocnemius muscles after sciatic nerve crush and transection. Real time PCR revealed that beta1,4-GalT I and V mRNAs expressed at a high level in normal gastrocnemius muscles and decreased gradually from 6 h, reached the lowest level at 2 weeks, then restored gradually to relatively normal level at 4 weeks after sciatic nerve crush. In contrast, in sciatic nerve transection model, beta1,4-GalT I and V mRNAs decreased gradually from 6 h, and remained on a low level at 4 weeks in gastrocnemius muscles after sciatic nerve transection. In situ hybridization indicated that beta1,4-GalT I and V mRNAs localized in numerous myocytes and muscle satellite cells under normal conditions and at 4 weeks after sciatic nerve crush, and in a few muscle satellite cells at 4 weeks after sciatic nerve transection. Furthermore, lectin blotting showed that the expression level of the Galbeta1-4GlcNAc group decreased from 6 h, reached the lowest level at 2 weeks, and restored to relatively normal level at 4 weeks after sciatic nerve crush. RCA-I lectin histochemistry demonstrated that Galbeta1-4GlcNAc group localized in numerous membranes of myocytes and muscle satellite cells in normal and at 4 weeks after sciatic nerve crush, and in a few muscle satellite cells at 2 and 4 weeks after sciatic nerve transection. These results indicated that the expressions of beta1,4-GalT I, V mRNAs and Galbeta1-4GlcNAc group were involved in the process of denervation and reinnervation, which suggests that beta1,4-GalT I, V mRNAs and Galbeta1-4GlcNAc group may play an important role in the muscle regeneration.
The Jiangsu Key Laboratory of Neuroregeneration, Nantong University, Nantong, Jiangsu Province, People's Republic of China. ymz@ntu.edu.cn
Meijuan
M
Yan
Chun
C
Cheng
Fei
F
Ding
Jing
J
Jiang
Lingling
L
Gao
Chunlin
C
Xia
Aiguo
A
Shen
D000606:Amino Sugars / Q000378:metabolism*; D000818:Animals; D005700:Galactosyltransferases / Q000235:genetics*; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D006023:Glycoproteins / Q000378:metabolism; D007273:Injections, Intramuscular; D018482:Muscle, Skeletal / Q000201:enzymology* / Q000294:innervation* / Q000473:pathology / Q000503:physiopathology; D037121:Plant Lectins / Q000378:metabolism; D010957:Plasmids / Q000008:administration & dosage / Q000494:pharmacology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D032496:Satellite Cells, Skeletal Muscle / Q000187:drug effects / Q000201:enzymology / Q000473:pathology; D020426:Sciatic Neuropathy / Q000201:enzymology* / Q000235:genetics* / Q000473:pathology / Q000503:physiopathology; D013997:Time Factors
D000606:Amino Sugars; D006023:Glycoproteins; D037121:Plant Lectins; D012333:RNA, Messenger; C017707:Ricinus communis agglutinin-1; D005700:Galactosyltransferases