Prenylation of RabGTPases, Their Delivery to Membranes, and Rab Recycling - Ras Superfamily Small G Proteins: Biology and Mechanisms 2 - page 9

Table 1.1 Overview of Rab-GEFs, their sites of localization and their localization mechanism
GEF Rab Localization Localizer(s)

TRAPP (Cai et al. 2007 ; Wang
et al. 2000 )

Rab1 ER-Golgi Sec23 (CopII)

Ric1/Rgp1 (Pusapati et al. 2012 ) Rab6 Golgi, cytosol Rab33b:GTP

Sec2 (Ortiz et al. 2002 ; Walch-
Solimena et al. 1997 )

Sec4 Secretory vesicles Ypt32:GTP, Sec15

(exocyst)

Rabin8 (Chiba et al. 2013 ; Hattula
et al. 2002 ; Knodler et al. 2010 )

Rab8 Cilia, cortical actin Rab11:GTP, Sec15

(exocyst),
Phosphatidylserine

Rabex5 (Horiuchi et al. 1997 ) Rab5 Early endosomes Rabaptin5,

ubiquitinylation

DrrA/SidM (Brombacher et al. 2009 ;
Machner and Isberg 2007 ; Murata
et al. 2006 )

Rab1 Legionella

containing vac-
uole/plasma
membrane

PI(4)P

Mon1/Ccz1 (Lachmann et al. 2012 ;
Nordmann et al. 2010 )

Ypt7/Rab7 Late endosomes Vps21(Rab5):GTP

DENND1A (Allaire et al. 2010 ;
Yoshimura et al. 2010 )

Rab35 Clathrin coated

pits, (plasma
membrane)

AP2

DENND5A/5B (Miserey-Lenkei
et al. 2007 ; Recacha et al. 2009 ;
Yoshimura et al. 2010 )

Rab39 Golgi Rab6:GTP

DENND2 (Yoshimura et al. 2010 ) Rab9 Actin filaments

lysosomal
trafficking

MADD/Rab3Gep (Figueiredo
et al. 2008 ; Yoshimura et al. 2010 )

Rab27 Melanosomes

Bloc-3 (Gerondopoulos et al. 2012 ) Rab32/38 Melanosomes

Crag (Xiong et al. 2012 ) Rab11 Rhabdomeres

FAM116 (Linford et al. 2012 ) Rab14 Recycling

endosomes,
cytosol

MTMR5/13 (Yoshimura et al. 2010 ) Rab28
DENND1C (Yoshimura et al. 2010 ) Rab13
DENND3 (Yoshimura et al. 2010 ) Rab12
DENND1B (Yoshimura et al. 2010 ) Rab35
In the case of recently discovered GEFs, this information is incomplete or absent

1.5 Do Additional Factors Contribute to Rab Targeting?

Although the evidence described is strong support for a decisive role of GEFs in
Rab targeting, over the years other factors have been suggested to play an important
part. The original hypothesis that the hypervariable C-terminal region alone acted
as the sole determining factor (Chavrier et al. 1991 ) has been challenged and at least
partially disproved, suggesting that multiple regions in Rabs contribute to mem-
brane targeting (Ali et al. 2004 ). However, further testing of the role of the