Data/hora: 06/06/2024 01:02:28

Provedor de dados: | 56
País: | Brazil
Título: | Evidence for the presence of a kininogen-like species in a case of total deficiency of low and high molecular weight kininogens
Autores: | Veloso,D.
Data: | 1998-07-01
Ano: | 1998
Palavras-chave: | Kininogen deficiency; Kinins; Antibodies; Plasma; Kininogen-like species; Human and nonhuman primates.
Resumo: | Low and high molecular weight kininogens (LK and HK), containing 409 and 626 amino acids with masses of ~65 and 120 kDa after glycosylation, respectively, are coded by a single gene mapped to the human chromosome 3 by alternative splicing of the transcribed mRNA. The NH2-termini Glu1-Thr383 region, identical in LK and HK, contains bradykinin (BK) moieties Arg363-Arg371. LK, HK and their kinin products Lys-BK and BK are involved in several biologic processes. They are evolutionarily conserved and only 7 patients, all apparently normal, have been reported to lack them. In one of these patients (Williams' trait), a codon mutation (Arg178 &lt;FONT FACE="Symbol"&gt;®&lt;/FONT&gt; stop) has been blamed for the absence of LK and HK. However, using Western blots with 2 monoclonal anti-HK antibodies, one that recognizes the region common to LK and HK and the other that recognizes only HK, I detected ~110-kDa bands in the plasma of this LK/HK-deficient patient vs ~120-kDa bands in normal human and ape plasmas. With polyclonal anti-Lys-BK antibody, which strongly detects BK cleaved at its COOH-terminus in purified HK, I detected ~110-kDa bands in the normal and the deficient plasmas. Western blots with a monoclonal anti-prekallikrein (PK) antibody showed that surface activation of PK and distribution of PK activation products, both dependent on HK, were similar in these plasmas. These findings suggest that a mutant gene yielded a kininogen-like species possibly involving aberrant mRNA splicing - structurally different from normal HK, but apparently with the capacity to carry out seemingly vital HK functions.
Tipo: | Info:eu-repo/semantics/article
Idioma: | Inglês
Identificador: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X1998000700004
Editor: | Associação Brasileira de Divulgação Científica
Relação: | 10.1590/S0100-879X1998000700004
Formato: | text/html
Fonte: | Brazilian Journal of Medical and Biological Research  v.31 n.7 1998
Fonte: | info:eu-repo/semantics/openAccess