PubMed:7937747 JSONTXT

{"project":"AIMed","denotations":[{"id":"T1","span":{"begin":34,"end":39},"obj":"protein"},{"id":"T2","span":{"begin":116,"end":121},"obj":"protein"},{"id":"T3","span":{"begin":167,"end":172},"obj":"protein"},{"id":"T4","span":{"begin":191,"end":198},"obj":"protein"},{"id":"T5","span":{"begin":200,"end":207},"obj":"protein"},{"id":"T6","span":{"begin":209,"end":214},"obj":"protein"},{"id":"T7","span":{"begin":220,"end":223},"obj":"protein"},{"id":"T8","span":{"begin":311,"end":316},"obj":"protein"},{"id":"T9","span":{"begin":622,"end":627},"obj":"protein"},{"id":"T10","span":{"begin":654,"end":659},"obj":"protein"},{"id":"T11","span":{"begin":681,"end":688},"obj":"protein"},{"id":"T12","span":{"begin":693,"end":698},"obj":"protein"},{"id":"T13","span":{"begin":732,"end":735},"obj":"protein"},{"id":"T14","span":{"begin":740,"end":747},"obj":"protein"},{"id":"T15","span":{"begin":749,"end":756},"obj":"protein"},{"id":"T16","span":{"begin":819,"end":824},"obj":"protein"},{"id":"T17","span":{"begin":844,"end":849},"obj":"protein"},{"id":"T18","span":{"begin":878,"end":883},"obj":"protein"},{"id":"T19","span":{"begin":899,"end":904},"obj":"protein"},{"id":"T20","span":{"begin":984,"end":989},"obj":"protein"},{"id":"T21","span":{"begin":1031,"end":1036},"obj":"protein"},{"id":"T22","span":{"begin":1126,"end":1131},"obj":"protein"},{"id":"T23","span":{"begin":1204,"end":1209},"obj":"protein"},{"id":"T24","span":{"begin":1250,"end":1255},"obj":"protein"},{"id":"T25","span":{"begin":1294,"end":1297},"obj":"protein"},{"id":"T26","span":{"begin":1398,"end":1403},"obj":"protein"},{"id":"T27","span":{"begin":1405,"end":1412},"obj":"protein"},{"id":"T28","span":{"begin":1417,"end":1422},"obj":"protein"},{"id":"T29","span":{"begin":1448,"end":1455},"obj":"protein"},{"id":"T30","span":{"begin":1490,"end":1495},"obj":"protein"},{"id":"T31","span":{"begin":1584,"end":1587},"obj":"protein"},{"id":"T32","span":{"begin":1592,"end":1599},"obj":"protein"},{"id":"T33","span":{"begin":1624,"end":1629},"obj":"protein"},{"id":"T34","span":{"begin":1675,"end":1680},"obj":"protein"},{"id":"T35","span":{"begin":1681,"end":1684},"obj":"protein"},{"id":"T36","span":{"begin":1736,"end":1741},"obj":"protein"},{"id":"T37","span":{"begin":1742,"end":1747},"obj":"protein"}],"text":"Interactions among members of the Bcl-2 protein family analyzed with a yeast two-hybrid system.\nInteractions of the Bcl-2 protein with itself and other members of the Bcl-2 family, including Bcl-X-L, Bcl-X-S, Mcl-1, and Bax, were explored with a yeast two-hybrid system. Fusion proteins were created by linking Bcl-2 family proteins to a LexA DNA-binding domain or a B42 trans-activation domain. Protein-protein interactions were examined by expression of these fusion proteins in Saccharomyces cerevisiae having a lacZ (beta-galactosidase) gene under control of a LexA-dependent operator. This approach gave evidence for Bcl-2 protein homodimerization. Bcl-2 also interacted with Bcl-X-L and Mcl-1 and with the dominant inhibitors Bax and Bcl-X-S. Bcl-X-L displayed the same pattern of combinatorial interactions with Bcl-2 family proteins as Bcl-2. Use of deletion mutants of Bcl-2 suggested that Bcl-2 homodimerization involves interactions between two distinct regions within the Bcl-2 protein, since a LexA protein containing Bcl-2 amino acids 83-218 mediated functional interactions with a B42 fusion protein containing Bcl-2 amino acids 1-81 but did not complement a B42 fusion protein containing Bcl-2 amino acids 83-218. In contrast to LexA/Bcl-2 fusion proteins, expression of a LexA/Bax protein was lethal to yeast. This cytotoxicity could be abrogated by B42 fusion proteins containing Bcl-2, Bcl-X-L, or Mcl-1 but not those containing Bcl-X-S (an alternatively spliced form of Bcl-X that lacks a well-conserved 63-amino acid region). The findings suggest a model whereby Bax and Bcl-X-S differentially regulate Bcl-2 function, and indicate that requirements for Bcl-2/Bax heterodimerization may be different from those for Bcl-2/Bcl-2 homodimerization."}