A PHP Error was encountered

Severity: Warning

Message: file_get_contents(https://...@gmail.com&api_key=61f08fa0b96a73de8c900d749fcb997acc09): Failed to open stream: HTTP request failed! HTTP/1.1 429 Too Many Requests

Filename: helpers/my_audit_helper.php

Line Number: 143

Backtrace:

File: /var/www/html/application/helpers/my_audit_helper.php
Line: 143
Function: file_get_contents

File: /var/www/html/application/helpers/my_audit_helper.php
Line: 209
Function: simplexml_load_file_from_url

File: /var/www/html/application/helpers/my_audit_helper.php
Line: 994
Function: getPubMedXML

File: /var/www/html/application/helpers/my_audit_helper.php
Line: 3134
Function: GetPubMedArticleOutput_2016

File: /var/www/html/application/controllers/Detail.php
Line: 574
Function: pubMedSearch_Global

File: /var/www/html/application/controllers/Detail.php
Line: 488
Function: pubMedGetRelatedKeyword

File: /var/www/html/index.php
Line: 316
Function: require_once

The yeast elongator histone acetylase requires Sit4-dependent dephosphorylation for toxin-target capacity. | LitMetric

AI Article Synopsis

  • Kluyveromyces lactis zymocin is a toxin that induces a G1 cell cycle block in Saccharomyces cerevisiae by requiring the holo-Elongator complex, which is a six-subunit enzyme involved in histone acetylation.
  • The main findings reveal that the largest subunit of Elongator (Tot1/Elp1) is regulated by phosphorylation, influenced by an Elongator-interactor called Kti11 and the phosphatase Sit4 along with its partners.
  • Manipulating the levels of Tot4 (Kti12) and Sit4 affects the phosphorylation state of Tot1, which is essential for zymocin's toxic effects while also highlighting their roles in cell cycle

Article Abstract

Kluyveromyces lactis zymocin, a heterotrimeric toxin complex, imposes a G1 cell cycle block on Saccharomyces cerevisiae that requires the toxin-target (TOT) function of holo-Elongator, a six-subunit histone acetylase. Here, we demonstrate that Elongator is a phospho-complex. Phosphorylation of its largest subunit Tot1 (Elp1) is supported by Kti11, an Elongator-interactor essential for zymocin action. Tot1 dephosphorylation depends on the Sit4 phosphatase and its associators Sap185 and Sap190. Zymocin-resistant cells lacking or overproducing Elongator-associator Tot4 (Kti12), respectively, abolish or intensify Tot1 phosphorylation. Excess Sit4.Sap190 antagonizes the latter scenario to reinstate zymocin sensitivity in multicopy TOT4 cells, suggesting physical competition between Sit4 and Tot4. Consistently, Sit4 and Tot4 mutually oppose Tot1 de-/phosphorylation, which is dispensable for integrity of holo-Elongator but crucial for the TOT-dependent G1 block by zymocin. Moreover, Sit4, Tot4, and Tot1 cofractionate, Sit4 is nucleocytoplasmically localized, and sit4Delta-nuclei retain Tot4. Together with the findings that sit4Delta and totDelta cells phenocopy protection against zymocin and the ceramide-induced G1 block, Sit4 is functionally linked to Elongator in cell cycle events targetable by antizymotics.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC363168PMC
http://dx.doi.org/10.1091/mbc.e03-10-0750DOI Listing

Publication Analysis

Top Keywords

sit4 tot4
12
histone acetylase
8
cell cycle
8
sit4
6
tot4
6
zymocin
5
tot1
5
yeast elongator
4
elongator histone
4
acetylase requires
4

Similar Publications

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!

A PHP Error was encountered

Severity: Notice

Message: fwrite(): Write of 34 bytes failed with errno=28 No space left on device

Filename: drivers/Session_files_driver.php

Line Number: 272

Backtrace:

A PHP Error was encountered

Severity: Warning

Message: session_write_close(): Failed to write session data using user defined save handler. (session.save_path: /var/lib/php/sessions)

Filename: Unknown

Line Number: 0

Backtrace: