Molecular organization of a gene in barley which encodes a protein similar to aspartic protease and its specific expression in nucellar cells during degeneration

Molecular organization of a gene in barley which encodes a protein similar to aspartic protease... The nucellar cells of barley undergo progressive degeneration after ovule fertilization. This degeneration is a characteristic of programmed cell death. Increasing evidence has indicated that proteases are important regulators of programmed cell death in animals. We have cloned and characterized a barley gene which encodes an aspartic protease-like protein and is specifically expressed in nucellar cells during degeneration. The gene contains eight exons and seven introns and encodes a polypeptide of 410 amino acid residues. The deduced polypeptide is characterized by having two aspartic protease catalytic site motifs, the Asp-Thr-Gly-Ser in the N-terminal and Asp-Ser-Gly-Ser in the C-terminal region, and two other regions nearly identical to two regions of plant aspartic proteases. However, it shares <20% overall sequence identity with the known plant aspartic proteases, and does not contain a ‘prosequence’ or a ‘plant-specific insert’ which are characteristics of plant aspartic proteases. We have named this aspartic protease-like protein ‘nucellin’. In northern analyses nucellin transcripts were most abundant in ovaries 3–4 days after pollination, but only marginally detectable before pollination or 10 days after pollination. RNA in situ hybridization showed that before pollination the nucellin gene was expressed at a very low level only in a cluster of nucellar cells close to the embryo sac at the chalazal end, but after pollination it was highly expressed in most nucellar cells surrounding the entire embryo sac. Furthermore, no nucellin transcripts were detectable in anther, leaf, or root tissue. The temporal and spatial pattern of the nucellin gene expression is synchronal with nucellar cell degeneration and thus, nucellin may be involved with nucellar cell death. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Plant Molecular Biology Springer Journals

Molecular organization of a gene in barley which encodes a protein similar to aspartic protease and its specific expression in nucellar cells during degeneration

Loading next page...
 
/lp/springer_journal/molecular-organization-of-a-gene-in-barley-which-encodes-a-protein-5tsEdsi5ir
Publisher
Kluwer Academic Publishers
Copyright
Copyright © 1997 by Kluwer Academic Publishers
Subject
Life Sciences; Biochemistry, general; Plant Sciences; Plant Pathology
ISSN
0167-4412
eISSN
1573-5028
D.O.I.
10.1023/A:1005833207707
Publisher site
See Article on Publisher Site

Abstract

The nucellar cells of barley undergo progressive degeneration after ovule fertilization. This degeneration is a characteristic of programmed cell death. Increasing evidence has indicated that proteases are important regulators of programmed cell death in animals. We have cloned and characterized a barley gene which encodes an aspartic protease-like protein and is specifically expressed in nucellar cells during degeneration. The gene contains eight exons and seven introns and encodes a polypeptide of 410 amino acid residues. The deduced polypeptide is characterized by having two aspartic protease catalytic site motifs, the Asp-Thr-Gly-Ser in the N-terminal and Asp-Ser-Gly-Ser in the C-terminal region, and two other regions nearly identical to two regions of plant aspartic proteases. However, it shares <20% overall sequence identity with the known plant aspartic proteases, and does not contain a ‘prosequence’ or a ‘plant-specific insert’ which are characteristics of plant aspartic proteases. We have named this aspartic protease-like protein ‘nucellin’. In northern analyses nucellin transcripts were most abundant in ovaries 3–4 days after pollination, but only marginally detectable before pollination or 10 days after pollination. RNA in situ hybridization showed that before pollination the nucellin gene was expressed at a very low level only in a cluster of nucellar cells close to the embryo sac at the chalazal end, but after pollination it was highly expressed in most nucellar cells surrounding the entire embryo sac. Furthermore, no nucellin transcripts were detectable in anther, leaf, or root tissue. The temporal and spatial pattern of the nucellin gene expression is synchronal with nucellar cell degeneration and thus, nucellin may be involved with nucellar cell death.

Journal

Plant Molecular BiologySpringer Journals

Published: Sep 30, 2004

References

You’re reading a free preview. Subscribe to read the entire article.


DeepDyve is your
personal research library

It’s your single place to instantly
discover and read the research
that matters to you.

Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.

All for just $49/month

Explore the DeepDyve Library

Search

Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly

Organize

Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.

Access

Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.

Your journals are on DeepDyve

Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.

All the latest content is available, no embargo periods.

See the journals in your area

DeepDyve

Freelancer

DeepDyve

Pro

Price

FREE

$49/month
$360/year

Save searches from
Google Scholar,
PubMed

Create lists to
organize your research

Export lists, citations

Read DeepDyve articles

Abstract access only

Unlimited access to over
18 million full-text articles

Print

20 pages / month

PDF Discount

20% off