High impact information on SMF3

• Smf3p is not regulated by Bsd2p or by manganese ions and is not degraded in the vacuole [1].
• Western analysis with antibody against Smf3p indicated that this transporter does not reach the plasma membrane and may function at the Golgi or post-Golgi complexes [2].
• Yeast membrane proteins SMF1, SMF2, and SMF3 are homologues of the DCT1 metal ion transporter family [3].
• Fet4p is not the only metal transporter that is negatively regulated by oxygen; we find that Rox1p also represses S. cerevisiae SMF3, proposed to function in vacuolar iron transport [4].
• Iron regulation of SMF3 was dramatically reduced, but not completely eliminated, in strains lacking both the AFT1 and AFT2 iron regulatory factors [5].

Biological context of SMF3

• Using SMF3-lacZ reporter constructs, we identified two distinct regions of the SMF3 promoter that contribute to iron regulation: (1) approx. nt -435 to -350 that contain dual consensus recognition sites for the Aft1 iron transcription factor; and (2) nt -348 to -247 that do not contain obvious Aft1 binding sites [5].

Anatomical context of SMF3

• SMF2 (but not SMF3) mediated significant increases in both Fe(2+) and Na(+) transport compared with control oocytes [3].

Other interactions of SMF3

• Smf1p and Smf2p are regulated at the post-translational level by manganese, whereas Smf3p is regulated by iron through a mechanism that, up until now, was unknown [5].

References