|
||
B2
By
From The Department of Oncology, Bristol-Myers Squibb Pharmaceutical Research Institute,
Princeton, New Jersey 08543-4000
The nfkb2 gene encodes the p100 precursor which produces the p52 protein after proteolytic
cleavage of its COOH-terminal domain. Although the p52 product can act as an alternative
subunit of NF-
B, the p100 precursor is believed to function as an inhibitor of Rel/NF-
B
activity by cytoplasmic retention of Rel/NF-
B complexes, like other members of the I
B
family. However, the physiological relevance of the p100 precursor as an I
B molecule has not
been understood. To assess the role of the precursor in vivo, we generated, by gene targeting,
mice lacking p100 but still containing a functional p52 protein. Mice with a homozygous deletion of the COOH-terminal ankyrin repeats of NF-
B2 (p100
/
) had marked gastric hyperplasia, resulting in early postnatal death. p100
/
animals also presented histopathological alterations of hematopoietic tissues, enlarged lymph nodes, increased lymphocyte proliferation in
response to several stimuli, and enhanced cytokine production in activated T cells. Dramatic
induction of nuclear
B-binding activity composed of p52-containing complexes was found in
all tissues examined and also in stimulated lymphocytes. Thus, the p100 precursor is essential
for the proper regulation of p52-containing Rel/NF-
B complexes in various cell types and its
absence cannot be efficiently compensated for by other I
B proteins.
This article has been cited by other articles:
| TABLE OF CONTENTS |
|