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Rab5 antibody - 108 011

Rab5 is a GTP-binding protein involved in endocytosis
Mouse monoclonal purified IgG
Cat. No.: 108 011
Amount: 100 µg
Price: $415.00
Cat. No. 108 011 100 µg purified IgG, lyophilized. Albumin and azide were added for stabilization. For reconstitution add 100 µl H2O to get a 1mg/ml solution in PBS. Then aliquot and store at -20°C to -80°C until use.
Antibodies should be stored at +4°C when still lyophilized. Do not freeze!
Applications
 
WB: 1 : 1000 up to 1 : 10000 (AP staining) gallery  
IP: yes
ICC: 1 : 100 up to 1 : 1000 (see remarks) gallery  
IHC: not tested yet
IHC-P: not tested yet
Clone 621.3
Subtype IgG2a (κ light chain)
Immunogen Recombinant protein corresponding to AA 1 to 215 from rat Rab5 (UniProt Id: O88565)
Reactivity Reacts with: human (Q9UJ41), rat (M0RC99), mouse (Q9JM13), hamster.
No signal: zebrafish.
Other species not tested yet.
Specificity Specific for rab 5 (probably only rab 5a). No cross-reactivity to other rab proteins.
Remarks

- Recommended for human samples.
- This antibody was used very successfully for immunoisolation of early endosomes and for the differentiation of early endosomes from related trafficking organelles in neurons and nonneuronal cells.
ICCNot suitable for ICC of aldehyde- fixed cells. Methanol fixation is recommended.

Data sheet 108_011.pdf

References for Rab5 - 108 011

Sugar transporter Slc37a2 regulates bone metabolism in mice via a tubular lysosomal network in osteoclasts.
Ng PY, Ribet ABP, Guo Q, Mullin BH, Tan JWY, Landao-Bassonga E, Stephens S, Chen K, Yuan J, Abudulai L, Bollen M, et al.
Nature communications (2023) 141: 906. 108 011 WB; tested species: mouse
The amyloid precursor protein is a conserved Wnt receptor.
Liu T, Zhang T, Nicolas M, Boussicault L, Rice H, Soldano A, Claeys A, Petrova I, Fradkin L, De Strooper B, Potier MC, et al.
eLife (2021) 10: . 108 011 WB, ICC; tested species: mouse
SNAREs define targeting specificity of trafficking vesicles by combinatorial interaction with tethering factors.
Koike S, Jahn R
Nature communications (2019) 101: 1608. 108 011 WB; tested species: human
Critical role for piccolo in synaptic vesicle retrieval.
Ackermann F, Schink KO, Bruns C, Izsvák Z, Hamra FK, Rosenmund C, Garner CC
eLife (2019) 8: . 108 011 WB, ICC; tested species: rat
Neuronal lysosomal dysfunction releases exosomes harboring APP C-terminal fragments and unique lipid signatures.
Miranda AM, Lasiecka ZM, Xu Y, Neufeld J, Shahriar S, Simoes S, Chan RB, Oliveira TG, Small SA, Di Paolo G
Nature communications (2018) 91: 291. 108 011 WB, ICC; tested species: mouse
Local detection of PtdIns3P at autophagosome biogenesis membrane platforms.
Nascimbeni AC, Codogno P, Morel E
Autophagy (2017) 139: 1602-1612. 108 011 WB; tested species: human
Parkinson Sac Domain Mutation in Synaptojanin 1 Impairs Clathrin Uncoating at Synapses and Triggers Dystrophic Changes in Dopaminergic Axons.
Cao M, Wu Y, Ashrafi G, McCartney AJ, Wheeler H, Bushong EA, Boassa D, Ellisman MH, Ryan TA, De Camilli P
Neuron (2017) 934: 882-896.e5. 108 011 WB; tested species: mouse
Dendritic Cell-Secreted Cytotoxic T-Lymphocyte-Associated Protein-4 Regulates the T-cell Response by Downmodulating Bystander Surface B7.
Halpert MM, Konduri V, Liang D, Chen Y, Wing JB, Paust S, Levitt JM, Decker WK
Stem cells and development (2016) 2510: 774-87. 108 011 WB, ICC; tested species: mouse
The serine/threonine kinase Ndr2 controls integrin trafficking and integrin-dependent neurite growth.
Rehberg K, Kliche S, Madencioglu DA, Thiere M, Müller B, Meineke BM, Freund C, Budinger E, Stork O
The Journal of neuroscience : the official journal of the Society for Neuroscience (2014) 3415: 5342-54. 108 011 WB, ICC
Composition of isolated synaptic boutons reveals the amounts of vesicle trafficking proteins.
Wilhelm BG, Mandad S, Truckenbrodt S, Kröhnert K, Schäfer C, Rammner B, Koo SJ, Claßen GA, Krauss M, Haucke V, Urlaub H, et al.
Science (New York, N.Y.) (2014) 3446187: 1023-8. 108 011 WB
Regulation of mammalian autophagy by class II and III PI 3-kinases through PI3P synthesis.
Devereaux K, Dall'Armi C, Alcazar-Roman A, Ogasawara Y, Zhou X, Wang F, Yamamoto A, De Camilli P, Di Paolo G
PloS one (2013) 810: e76405. 108 011 WB; tested species: mouse
Small-scale isolation of synaptic vesicles from mammalian brain.
Ahmed S, Holt M, Riedel D, Jahn R
Nature protocols (2013) 85: 998-1009. 108 011 WB; tested species: mouse
Comparative lipidomics analysis of HIV-1 particles and their producer cell membrane in different cell lines.
Lorizate M, Sachsenheimer T, Glass B, Habermann A, Gerl MJ, Kräusslich HG, Brügger B
Cellular microbiology (2013) 152: 292-304. 108 011 WB
CSPα knockout causes neurodegeneration by impairing SNAP-25 function.
Sharma M, Burré J, Bronk P, Zhang Y, Xu W, Südhof TC
The EMBO journal (2012) 314: 829-41. 108 011 WB; tested species: mouse
Quantitative analysis of synaptic vesicle Rabs uncovers distinct yet overlapping roles for Rab3a and Rab27b in Ca2+-triggered exocytosis.
Pavlos NJ, Grønborg M, Riedel D, Chua JJ, Boyken J, Kloepper TH, Urlaub H, Rizzoli SO, Jahn R
The Journal of neuroscience : the official journal of the Society for Neuroscience (2010) 3040: 13441-53. 108 011 WB, ICC
Localization to mature melanosomes by virtue of cytoplasmic dileucine motifs is required for human OCA2 function.
Sitaram A, Piccirillo R, Palmisano I, Harper DC, Dell'Angelica EC, Schiaffino MV, Marks MS
Molecular biology of the cell (2009) 205: 1464-77. 108 011 WB
Rab5 and Rab7 control endocytic sorting along the axonal retrograde transport pathway.
Deinhardt K, Salinas S, Verastegui C, Watson R, Worth D, Hanrahan S, Bucci C, Schiavo G
Neuron (2006) 522: 293-305. 108 011 ICC, WB
Neurotransmitter release regulated by a MALS-liprin-alpha presynaptic complex.
Olsen O, Moore KA, Fukata M, Kazuta T, Trinidad JC, Kauer FW, Streuli M, Misawa H, Burlingame AL, Nicoll RA, Bredt DS, et al.
The Journal of cell biology (2005) 1707: 1127-34. 108 011 WB
SNARE proteins are highly enriched in lipid rafts in PC12 cells: implications for the spatial control of exocytosis.
Chamberlain LH, Burgoyne RD, Gould GW
Proceedings of the National Academy of Sciences of the United States of America (2001) 9810: 5619-24. 108 011 WB
The R-SNARE endobrevin/VAMP-8 mediates homotypic fusion of early endosomes and late endosomes.
Antonin W, Holroyd C, Tikkanen R, Höning S, Jahn R
Molecular biology of the cell (2000) 1110: 3289-98. 108 011 WB
Synaptic and vesicular coexistence of VGLUT and VGAT in selected excitatory and inhibitory synapses.
Zander JF, Münster-Wandowski A, Brunk I, Pahner I, Gómez-Lira G, Heinemann U, Gutiérrez R, Laube G, Ahnert-Hilger G
The Journal of neuroscience : the official journal of the Society for Neuroscience (2010) 3022: 7634-45. 108 011 IP
Sunday driver interacts with two distinct classes of axonal organelles.
Abe N, Almenar-Queralt A, Lillo C, Shen Z, Lozach J, Briggs SP, Williams DS, Goldstein LS, Cavalli V
The Journal of biological chemistry (2009) 28450: 34628-39. 108 011 IP
Localization versus function of Rab3 proteins. Evidence for a common regulatory role in controlling fusion.
Schlüter OM, Khvotchev M, Jahn R, Südhof TC
The Journal of biological chemistry (2002) 27743: 40919-29. 108 011 IP
The amyloid precursor protein is a conserved Wnt receptor.
Liu T, Zhang T, Nicolas M, Boussicault L, Rice H, Soldano A, Claeys A, Petrova I, Fradkin L, De Strooper B, Potier MC, et al.
eLife (2021) 10: . 108 011 WB, ICC; tested species: mouse
MHC class I and II peptide homology regulates the cellular immune response.
Halpert MM, Konduri V, Liang D, Vazquez-Perez J, Hofferek CJ, Weldon SA, Baig Y, Vedula I, Levitt JM, Decker WK
FASEB journal : official publication of the Federation of American Societies for Experimental Biology (2020) : . 108 011 ICC; tested species: mouse
CtBP1-Mediated Membrane Fission Contributes to Effective Recycling of Synaptic Vesicles.
Ivanova D, Imig C, Camacho M, Reinhold A, Guhathakurta D, Montenegro-Venegas C, Cousin MA, Gundelfinger ED, Rosenmund C, Cooper B, Fejtova A, et al.
Cell reports (2020) 307: 2444-2459.e7. 108 011 ICC; tested species: mouse
Depletion of the AD Risk Gene SORL1 Selectively Impairs Neuronal Endosomal Traffic Independent of Amyloidogenic APP Processing.
Knupp A, Mishra S, Martinez R, Braggin JE, Szabo M, Kinoshita C, Hailey DW, Small SA, Jayadev S, Young JE
Cell reports (2020) 319: 107719. 108 011 ICC; tested species: human
Critical role for piccolo in synaptic vesicle retrieval.
Ackermann F, Schink KO, Bruns C, Izsvák Z, Hamra FK, Rosenmund C, Garner CC
eLife (2019) 8: . 108 011 WB, ICC; tested species: rat
Neuronal lysosomal dysfunction releases exosomes harboring APP C-terminal fragments and unique lipid signatures.
Miranda AM, Lasiecka ZM, Xu Y, Neufeld J, Shahriar S, Simoes S, Chan RB, Oliveira TG, Small SA, Di Paolo G
Nature communications (2018) 91: 291. 108 011 WB, ICC; tested species: mouse
Arf6 regulates the cycling and the readily releasable pool of synaptic vesicles at hippocampal synapse.
Tagliatti E, Fadda M, Falace A, Benfenati F, Fassio A
eLife (2016) 5: . 108 011 ICC; tested species: rat
Dendritic Cell-Secreted Cytotoxic T-Lymphocyte-Associated Protein-4 Regulates the T-cell Response by Downmodulating Bystander Surface B7.
Halpert MM, Konduri V, Liang D, Chen Y, Wing JB, Paust S, Levitt JM, Decker WK
Stem cells and development (2016) 2510: 774-87. 108 011 WB, ICC; tested species: mouse
Optogenetic acidification of synaptic vesicles and lysosomes.
Rost BR, Schneider F, Grauel MK, Wozny C, Bentz C, Blessing A, Rosenmund T, Jentsch TJ, Schmitz D, Hegemann P, Rosenmund C, et al.
Nature neuroscience (2015) 1812: 1845-1852. 108 011 ICC; tested species: human
The serine/threonine kinase Ndr2 controls integrin trafficking and integrin-dependent neurite growth.
Rehberg K, Kliche S, Madencioglu DA, Thiere M, Müller B, Meineke BM, Freund C, Budinger E, Stork O
The Journal of neuroscience : the official journal of the Society for Neuroscience (2014) 3415: 5342-54. 108 011 WB, ICC
Quantitative analysis of synaptic vesicle Rabs uncovers distinct yet overlapping roles for Rab3a and Rab27b in Ca2+-triggered exocytosis.
Pavlos NJ, Grønborg M, Riedel D, Chua JJ, Boyken J, Kloepper TH, Urlaub H, Rizzoli SO, Jahn R
The Journal of neuroscience : the official journal of the Society for Neuroscience (2010) 3040: 13441-53. 108 011 WB, ICC
Rab5 and Rab7 control endocytic sorting along the axonal retrograde transport pathway.
Deinhardt K, Salinas S, Verastegui C, Watson R, Worth D, Hanrahan S, Bucci C, Schiavo G
Neuron (2006) 522: 293-305. 108 011 ICC, WB
Endosomal sorting of readily releasable synaptic vesicles.
Hoopmann P, Punge A, Barysch SV, Westphal V, Bückers J, Opazo F, Bethani I, Lauterbach MA, Hell SW, Rizzoli SO
Proceedings of the National Academy of Sciences of the United States of America (2010) 10744: 19055-60. 108 011
Cat. No.: 108 011
Amount: 100 µg
Price: $415.00
Sugar transporter Slc37a2 regulates bone metabolism in mice via a tubular lysosomal network in osteoclasts.
Ng PY, Ribet ABP, Guo Q, Mullin BH, Tan JWY, Landao-Bassonga E, Stephens S, Chen K, Yuan J, Abudulai L, Bollen M, et al.
Nature communications (2023) 141: 906. 108 011 WB; tested species: mouse
The amyloid precursor protein is a conserved Wnt receptor.
Liu T, Zhang T, Nicolas M, Boussicault L, Rice H, Soldano A, Claeys A, Petrova I, Fradkin L, De Strooper B, Potier MC, et al.
eLife (2021) 10: . 108 011 WB, ICC; tested species: mouse
SNAREs define targeting specificity of trafficking vesicles by combinatorial interaction with tethering factors.
Koike S, Jahn R
Nature communications (2019) 101: 1608. 108 011 WB; tested species: human
Critical role for piccolo in synaptic vesicle retrieval.
Ackermann F, Schink KO, Bruns C, Izsvák Z, Hamra FK, Rosenmund C, Garner CC
eLife (2019) 8: . 108 011 WB, ICC; tested species: rat
Neuronal lysosomal dysfunction releases exosomes harboring APP C-terminal fragments and unique lipid signatures.
Miranda AM, Lasiecka ZM, Xu Y, Neufeld J, Shahriar S, Simoes S, Chan RB, Oliveira TG, Small SA, Di Paolo G
Nature communications (2018) 91: 291. 108 011 WB, ICC; tested species: mouse
Local detection of PtdIns3P at autophagosome biogenesis membrane platforms.
Nascimbeni AC, Codogno P, Morel E
Autophagy (2017) 139: 1602-1612. 108 011 WB; tested species: human
Parkinson Sac Domain Mutation in Synaptojanin 1 Impairs Clathrin Uncoating at Synapses and Triggers Dystrophic Changes in Dopaminergic Axons.
Cao M, Wu Y, Ashrafi G, McCartney AJ, Wheeler H, Bushong EA, Boassa D, Ellisman MH, Ryan TA, De Camilli P
Neuron (2017) 934: 882-896.e5. 108 011 WB; tested species: mouse
Dendritic Cell-Secreted Cytotoxic T-Lymphocyte-Associated Protein-4 Regulates the T-cell Response by Downmodulating Bystander Surface B7.
Halpert MM, Konduri V, Liang D, Chen Y, Wing JB, Paust S, Levitt JM, Decker WK
Stem cells and development (2016) 2510: 774-87. 108 011 WB, ICC; tested species: mouse
The serine/threonine kinase Ndr2 controls integrin trafficking and integrin-dependent neurite growth.
Rehberg K, Kliche S, Madencioglu DA, Thiere M, Müller B, Meineke BM, Freund C, Budinger E, Stork O
The Journal of neuroscience : the official journal of the Society for Neuroscience (2014) 3415: 5342-54. 108 011 WB, ICC
Composition of isolated synaptic boutons reveals the amounts of vesicle trafficking proteins.
Wilhelm BG, Mandad S, Truckenbrodt S, Kröhnert K, Schäfer C, Rammner B, Koo SJ, Claßen GA, Krauss M, Haucke V, Urlaub H, et al.
Science (New York, N.Y.) (2014) 3446187: 1023-8. 108 011 WB
Regulation of mammalian autophagy by class II and III PI 3-kinases through PI3P synthesis.
Devereaux K, Dall'Armi C, Alcazar-Roman A, Ogasawara Y, Zhou X, Wang F, Yamamoto A, De Camilli P, Di Paolo G
PloS one (2013) 810: e76405. 108 011 WB; tested species: mouse
Small-scale isolation of synaptic vesicles from mammalian brain.
Ahmed S, Holt M, Riedel D, Jahn R
Nature protocols (2013) 85: 998-1009. 108 011 WB; tested species: mouse
Comparative lipidomics analysis of HIV-1 particles and their producer cell membrane in different cell lines.
Lorizate M, Sachsenheimer T, Glass B, Habermann A, Gerl MJ, Kräusslich HG, Brügger B
Cellular microbiology (2013) 152: 292-304. 108 011 WB
CSPα knockout causes neurodegeneration by impairing SNAP-25 function.
Sharma M, Burré J, Bronk P, Zhang Y, Xu W, Südhof TC
The EMBO journal (2012) 314: 829-41. 108 011 WB; tested species: mouse
Quantitative analysis of synaptic vesicle Rabs uncovers distinct yet overlapping roles for Rab3a and Rab27b in Ca2+-triggered exocytosis.
Pavlos NJ, Grønborg M, Riedel D, Chua JJ, Boyken J, Kloepper TH, Urlaub H, Rizzoli SO, Jahn R
The Journal of neuroscience : the official journal of the Society for Neuroscience (2010) 3040: 13441-53. 108 011 WB, ICC
Localization to mature melanosomes by virtue of cytoplasmic dileucine motifs is required for human OCA2 function.
Sitaram A, Piccirillo R, Palmisano I, Harper DC, Dell'Angelica EC, Schiaffino MV, Marks MS
Molecular biology of the cell (2009) 205: 1464-77. 108 011 WB
Rab5 and Rab7 control endocytic sorting along the axonal retrograde transport pathway.
Deinhardt K, Salinas S, Verastegui C, Watson R, Worth D, Hanrahan S, Bucci C, Schiavo G
Neuron (2006) 522: 293-305. 108 011 ICC, WB
Neurotransmitter release regulated by a MALS-liprin-alpha presynaptic complex.
Olsen O, Moore KA, Fukata M, Kazuta T, Trinidad JC, Kauer FW, Streuli M, Misawa H, Burlingame AL, Nicoll RA, Bredt DS, et al.
The Journal of cell biology (2005) 1707: 1127-34. 108 011 WB
SNARE proteins are highly enriched in lipid rafts in PC12 cells: implications for the spatial control of exocytosis.
Chamberlain LH, Burgoyne RD, Gould GW
Proceedings of the National Academy of Sciences of the United States of America (2001) 9810: 5619-24. 108 011 WB
The R-SNARE endobrevin/VAMP-8 mediates homotypic fusion of early endosomes and late endosomes.
Antonin W, Holroyd C, Tikkanen R, Höning S, Jahn R
Molecular biology of the cell (2000) 1110: 3289-98. 108 011 WB
Synaptic and vesicular coexistence of VGLUT and VGAT in selected excitatory and inhibitory synapses.
Zander JF, Münster-Wandowski A, Brunk I, Pahner I, Gómez-Lira G, Heinemann U, Gutiérrez R, Laube G, Ahnert-Hilger G
The Journal of neuroscience : the official journal of the Society for Neuroscience (2010) 3022: 7634-45. 108 011 IP
Sunday driver interacts with two distinct classes of axonal organelles.
Abe N, Almenar-Queralt A, Lillo C, Shen Z, Lozach J, Briggs SP, Williams DS, Goldstein LS, Cavalli V
The Journal of biological chemistry (2009) 28450: 34628-39. 108 011 IP
Localization versus function of Rab3 proteins. Evidence for a common regulatory role in controlling fusion.
Schlüter OM, Khvotchev M, Jahn R, Südhof TC
The Journal of biological chemistry (2002) 27743: 40919-29. 108 011 IP
The amyloid precursor protein is a conserved Wnt receptor.
Liu T, Zhang T, Nicolas M, Boussicault L, Rice H, Soldano A, Claeys A, Petrova I, Fradkin L, De Strooper B, Potier MC, et al.
eLife (2021) 10: . 108 011 WB, ICC; tested species: mouse
MHC class I and II peptide homology regulates the cellular immune response.
Halpert MM, Konduri V, Liang D, Vazquez-Perez J, Hofferek CJ, Weldon SA, Baig Y, Vedula I, Levitt JM, Decker WK
FASEB journal : official publication of the Federation of American Societies for Experimental Biology (2020) : . 108 011 ICC; tested species: mouse
CtBP1-Mediated Membrane Fission Contributes to Effective Recycling of Synaptic Vesicles.
Ivanova D, Imig C, Camacho M, Reinhold A, Guhathakurta D, Montenegro-Venegas C, Cousin MA, Gundelfinger ED, Rosenmund C, Cooper B, Fejtova A, et al.
Cell reports (2020) 307: 2444-2459.e7. 108 011 ICC; tested species: mouse
Depletion of the AD Risk Gene SORL1 Selectively Impairs Neuronal Endosomal Traffic Independent of Amyloidogenic APP Processing.
Knupp A, Mishra S, Martinez R, Braggin JE, Szabo M, Kinoshita C, Hailey DW, Small SA, Jayadev S, Young JE
Cell reports (2020) 319: 107719. 108 011 ICC; tested species: human
Critical role for piccolo in synaptic vesicle retrieval.
Ackermann F, Schink KO, Bruns C, Izsvák Z, Hamra FK, Rosenmund C, Garner CC
eLife (2019) 8: . 108 011 WB, ICC; tested species: rat
Neuronal lysosomal dysfunction releases exosomes harboring APP C-terminal fragments and unique lipid signatures.
Miranda AM, Lasiecka ZM, Xu Y, Neufeld J, Shahriar S, Simoes S, Chan RB, Oliveira TG, Small SA, Di Paolo G
Nature communications (2018) 91: 291. 108 011 WB, ICC; tested species: mouse
Arf6 regulates the cycling and the readily releasable pool of synaptic vesicles at hippocampal synapse.
Tagliatti E, Fadda M, Falace A, Benfenati F, Fassio A
eLife (2016) 5: . 108 011 ICC; tested species: rat
Dendritic Cell-Secreted Cytotoxic T-Lymphocyte-Associated Protein-4 Regulates the T-cell Response by Downmodulating Bystander Surface B7.
Halpert MM, Konduri V, Liang D, Chen Y, Wing JB, Paust S, Levitt JM, Decker WK
Stem cells and development (2016) 2510: 774-87. 108 011 WB, ICC; tested species: mouse
Optogenetic acidification of synaptic vesicles and lysosomes.
Rost BR, Schneider F, Grauel MK, Wozny C, Bentz C, Blessing A, Rosenmund T, Jentsch TJ, Schmitz D, Hegemann P, Rosenmund C, et al.
Nature neuroscience (2015) 1812: 1845-1852. 108 011 ICC; tested species: human
The serine/threonine kinase Ndr2 controls integrin trafficking and integrin-dependent neurite growth.
Rehberg K, Kliche S, Madencioglu DA, Thiere M, Müller B, Meineke BM, Freund C, Budinger E, Stork O
The Journal of neuroscience : the official journal of the Society for Neuroscience (2014) 3415: 5342-54. 108 011 WB, ICC
Quantitative analysis of synaptic vesicle Rabs uncovers distinct yet overlapping roles for Rab3a and Rab27b in Ca2+-triggered exocytosis.
Pavlos NJ, Grønborg M, Riedel D, Chua JJ, Boyken J, Kloepper TH, Urlaub H, Rizzoli SO, Jahn R
The Journal of neuroscience : the official journal of the Society for Neuroscience (2010) 3040: 13441-53. 108 011 WB, ICC
Rab5 and Rab7 control endocytic sorting along the axonal retrograde transport pathway.
Deinhardt K, Salinas S, Verastegui C, Watson R, Worth D, Hanrahan S, Bucci C, Schiavo G
Neuron (2006) 522: 293-305. 108 011 ICC, WB
Endosomal sorting of readily releasable synaptic vesicles.
Hoopmann P, Punge A, Barysch SV, Westphal V, Bückers J, Opazo F, Bethani I, Lauterbach MA, Hell SW, Rizzoli SO
Proceedings of the National Academy of Sciences of the United States of America (2010) 10744: 19055-60. 108 011
Background
Rab 5 is a member of the Rab protein family that belongs to the ras-related superfamily of small monomeric GTPases. Rab 5 is ubiquitously expressed in all tissues where it functions in the fusion of early endosomes which is the first fusion step of endocytic organelles after their formation and detachment from the plasma membrane. It is presently the best marker with selectivity for this compartment.