Limits...
Selection against glycosylation in ruminant pancreatic ribonucleases by replacements in the ancestral carbohydrate attachment site.

Gautschi M, Beintema JJ - Biochem. Genet. (2008)

Bottom Line: A hypothesis, proposed 25 years ago, that there is selection against glycosylation in ruminant pancreatic ribonucleases by replacement of methionine to leucine in the ancestral carbohydrate attachment site Asn-Met-Thr at residues 34-36, was experimentally confirmed.The replacement of leucine at position 35 by methionine in bovine ribonuclease resulted in a three-fold relative increase in glycosylation when expressed in Chinese hamster ovary cells.

View Article: PubMed Central - PubMed

Affiliation: Institute of Molecular Biology and Biophysics, Schafmattstrasse 20, ETH-Hönggerberg, HPKE 14, 8093, Zurich, Switzerland.

ABSTRACT
A hypothesis, proposed 25 years ago, that there is selection against glycosylation in ruminant pancreatic ribonucleases by replacement of methionine to leucine in the ancestral carbohydrate attachment site Asn-Met-Thr at residues 34-36, was experimentally confirmed. The replacement of leucine at position 35 by methionine in bovine ribonuclease resulted in a three-fold relative increase in glycosylation when expressed in Chinese hamster ovary cells.

Show MeSH
Amino acid sequences of the carbohydrate attachment site 34–36 in RNases 1 from true ruminants and in several ancestors. Completely glycosylated sequences are in bold letters; partly glycosylated sequences are in bold italic letters. This figure was published in Beintema and Lenstra (1982) and also shows the topology of part of the RNase tree presented in this publication, which did not yet include the RNase sequence of the primitive ruminant chevrotain (Tragulus javanicus) with the nonglycosylated sequence Ser–Met–Thr (Breukelman et al. 2001)
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC2480611&req=5

Fig1: Amino acid sequences of the carbohydrate attachment site 34–36 in RNases 1 from true ruminants and in several ancestors. Completely glycosylated sequences are in bold letters; partly glycosylated sequences are in bold italic letters. This figure was published in Beintema and Lenstra (1982) and also shows the topology of part of the RNase tree presented in this publication, which did not yet include the RNase sequence of the primitive ruminant chevrotain (Tragulus javanicus) with the nonglycosylated sequence Ser–Met–Thr (Breukelman et al. 2001)

Mentions: Our studies on the molecular evolution of RNases 1 included 18 sequences from ruminant species (Pecora). Figure 1 shows the sequences of residues 34–36 in the ruminant part of an evolutionary tree of RNases 1 (Beintema and Lenstra 1982). Ten of the 18 sequences have Asn–Leu–Thr at these positions with minor glycosylation at eight sequences (bold italic letters). Much carbohydrate attached to all molecules in Asn–Leu–Thr occurs only in the RNases from giraffe and moose (normal bold letters). In seven of the other eight sequences Asn-34 is replaced by another residue, resulting in no glycosylation at this site. In six of these, position 35 is occupied by Met, the ancestral residue at this position. It is important to note that in nonruminant mammalian RNases 1 the ancestral sequence Met–Thr (35–36) is conserved (Beintema and Lenstra 1982).Fig. 1


Selection against glycosylation in ruminant pancreatic ribonucleases by replacements in the ancestral carbohydrate attachment site.

Gautschi M, Beintema JJ - Biochem. Genet. (2008)

Amino acid sequences of the carbohydrate attachment site 34–36 in RNases 1 from true ruminants and in several ancestors. Completely glycosylated sequences are in bold letters; partly glycosylated sequences are in bold italic letters. This figure was published in Beintema and Lenstra (1982) and also shows the topology of part of the RNase tree presented in this publication, which did not yet include the RNase sequence of the primitive ruminant chevrotain (Tragulus javanicus) with the nonglycosylated sequence Ser–Met–Thr (Breukelman et al. 2001)
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2480611&req=5

Fig1: Amino acid sequences of the carbohydrate attachment site 34–36 in RNases 1 from true ruminants and in several ancestors. Completely glycosylated sequences are in bold letters; partly glycosylated sequences are in bold italic letters. This figure was published in Beintema and Lenstra (1982) and also shows the topology of part of the RNase tree presented in this publication, which did not yet include the RNase sequence of the primitive ruminant chevrotain (Tragulus javanicus) with the nonglycosylated sequence Ser–Met–Thr (Breukelman et al. 2001)
Mentions: Our studies on the molecular evolution of RNases 1 included 18 sequences from ruminant species (Pecora). Figure 1 shows the sequences of residues 34–36 in the ruminant part of an evolutionary tree of RNases 1 (Beintema and Lenstra 1982). Ten of the 18 sequences have Asn–Leu–Thr at these positions with minor glycosylation at eight sequences (bold italic letters). Much carbohydrate attached to all molecules in Asn–Leu–Thr occurs only in the RNases from giraffe and moose (normal bold letters). In seven of the other eight sequences Asn-34 is replaced by another residue, resulting in no glycosylation at this site. In six of these, position 35 is occupied by Met, the ancestral residue at this position. It is important to note that in nonruminant mammalian RNases 1 the ancestral sequence Met–Thr (35–36) is conserved (Beintema and Lenstra 1982).Fig. 1

Bottom Line: A hypothesis, proposed 25 years ago, that there is selection against glycosylation in ruminant pancreatic ribonucleases by replacement of methionine to leucine in the ancestral carbohydrate attachment site Asn-Met-Thr at residues 34-36, was experimentally confirmed.The replacement of leucine at position 35 by methionine in bovine ribonuclease resulted in a three-fold relative increase in glycosylation when expressed in Chinese hamster ovary cells.

View Article: PubMed Central - PubMed

Affiliation: Institute of Molecular Biology and Biophysics, Schafmattstrasse 20, ETH-Hönggerberg, HPKE 14, 8093, Zurich, Switzerland.

ABSTRACT
A hypothesis, proposed 25 years ago, that there is selection against glycosylation in ruminant pancreatic ribonucleases by replacement of methionine to leucine in the ancestral carbohydrate attachment site Asn-Met-Thr at residues 34-36, was experimentally confirmed. The replacement of leucine at position 35 by methionine in bovine ribonuclease resulted in a three-fold relative increase in glycosylation when expressed in Chinese hamster ovary cells.

Show MeSH