ALF1/YNL148C Summary Help

Standard Name ALF1
Systematic Name YNL148C
Feature Type ORF, Verified
Description Alpha-tubulin folding protein; similar to mammalian cofactor B; Alf1p-GFP localizes to cytoplasmic microtubules; required for the folding of alpha-tubulin and may play an additional role in microtubule maintenance (1 and see Summary Paragraph)
Name Description ALpha-tubulin Foldin
Chromosomal Location
ChrXIV:350671 to 349907 | ORF Map | GBrowse
Note: this feature is encoded on the Crick strand.
Gene Ontology Annotations All ALF1 GO evidence and references
  View Computational GO annotations for ALF1
Molecular Function
Manually curated
Biological Process
Manually curated
Cellular Component
Regulators 3 genes
Classical genetics
Large-scale survey
29 total interaction(s) for 23 unique genes/features.
Physical Interactions
  • Affinity Capture-RNA: 2
  • Affinity Capture-Western: 3
  • Reconstituted Complex: 1
  • Two-hybrid: 3

Genetic Interactions
  • Dosage Lethality: 1
  • Dosage Rescue: 1
  • Phenotypic Enhancement: 6
  • Positive Genetic: 1
  • Synthetic Growth Defect: 5
  • Synthetic Lethality: 4
  • Synthetic Rescue: 2

Expression Summary
Length (a.a.) 254
Molecular Weight (Da) 28,353
Isoelectric Point (pI) 4.6
Phosphorylation PhosphoGRID | PhosphoPep Database
sequence information
ChrXIV:350671 to 349907 | ORF Map | GBrowse
Note: this feature is encoded on the Crick strand.
Last Update Coordinates: 2011-02-03 | Sequence: 1996-07-31
Subfeature details
Most Recent Updates
Coordinates Sequence
CDS 1..765 350671..349907 2011-02-03 1996-07-31
Retrieve sequences
Analyze Sequence
S288C only
S288C vs. other species
S288C vs. other strains
External Links All Associated Seq | Entrez Gene | Entrez RefSeq Protein | MIPS | Search all NCBI (Entrez) | UniProtKB
Primary SGDIDS000005092

Microtubules are conserved cytoskeletal elements that form by the polymerization of alpha- and beta-tubulin heterodimers. The formation of polymerization-competent tubulin heterodimers requires that alpha-tubulin and beta-tubulin be properly folded. Specific cofactors are required for the folding of alpha- and beta-tubulin in vitro and homologs of these cofactors have been found in many organisms, including S. cerevisiae (reviewed in 2).

In S. cerevisiae, ALF1 is a non-essential gene that is homologous to mammalian cofactor B 3, 1. In vitro, cofactor B acts in the post-chaperonin folding of alpha-tubulin 3. Consistent with in vitro studies, Alf1p genetically acts upstream of Pac2p/cofactor E 3, 1. ALF1 genetically interacts with the other tubulin cofactors (CIN1/cofactor D, RBL2/cofactor A), and is essential in combination with specific alpha-tubulin mutants 3, 1. alf1 null mutants are super-sensitive to benomyl, a microtubule depolymerizing drug 1.

Alf1p interacts with alpha-tubulin in the yeast two-hybrid and immunoprecipitation assays 1. Alf1p and cofactor B both contain a single CLIP-170 domain, which is found in several microtubule-associated proteins and is required for the Alf1p-alpha-tubulin interaction 1. Alf1p binds to a face of alpha-tubulin distinct of that of beta-tubulin binding 1. Alf1p-GFP localizes to cytoplasmic microtubules, suggesting that Alf1p may play an additional role in microtubule maintenance 1.

Last updated: 2003-08-28 Contact SGD

References cited on this page View Complete Literature Guide for ALF1
1) Feierbach B, et al.  (1999) Alf1p, a CLIP-170 domain-containing protein, is functionally and physically associated with alpha-tubulin. J Cell Biol 144(1):113-24
2) Lopez-Fanarraga M, et al.  (2001) Review: postchaperonin tubulin folding cofactors and their role in microtubule dynamics. J Struct Biol 135(2):219-29
3) Tian G, et al.  (1997) Tubulin subunits exist in an activated conformational state generated and maintained by protein cofactors. J Cell Biol 138(4):821-32