FlyBase Allele Report: Dmel\Marf[B]

General Information

Symbol

Dmel\Marf^B

Species

D. melanogaster

Name

FlyBase ID

FBal0299659

Feature type

allele

Associated gene

Dmel\Marf

Associated Insertion(s)

Carried in Construct

Key Links

Genomic Maps

JBrowse

Allele class

amorphic allele - genetic evidence

Mutagen

ethyl methanesulfonate

Nature of the Allele

Allele class

amorphic allele - genetic evidence

(Sandoval et al., 2014)

Mutagen

ethyl methanesulfonate

(Graves et al., 2020, Sandoval et al., 2014)

Progenitor genotype

Cytology

Description

Revision of data reported in FBrf0226654.

(Sandoval, 2015.5.4)

Amino acid replacement: I221N.

(Sandoval, 2015.5.4)

Mutations Mapped to the Genome

Curation Data

Type

Location

Additional Notes

References

point_mutation

X:6,367,783..6,367,783 [+]

Nucleotide change:

T6367783A

Amino acid change:

I221N | Marf-PB; I221N | Marf-PC; I221N | Marf-PD

Reported amino acid change:

I221N

Comment:

Site of nucleotide substitution in mutant inferred by FlyBase based on reported amino acid change.

(Sandoval, 2015.5.4)

Variant Molecular Consequences

Associated Sequence Data

DDBJ / EMBL / GenBank

DNA sequence

Protein sequence

UniProtKB/Swiss-Prot

UniProtKB/TrEMBL

Expression Data

Reporter Expression

Additional Information

Statement

Reference

Marker for

Reflects expression of

Reporter construct used in assay

Human Disease Associations

Disease Ontology (DO) Annotations

Models Based on Experimental Evidence ( 1 )

Disease

Evidence

References

model of Charcot-Marie-Tooth disease

CEA

(Sandoval et al., 2014)

Modifiers Based on Experimental Evidence ( 0 )

Disease

Interaction

References

Comments on Models/Modifiers Based on Experimental Evidence ( 0 )

Disease-implicated variant(s)

Phenotypic Data

Phenotypic Class

Phenotype Manifest In

Detailed Description

Statement

Reference

Whole-eye Marf^B mutant clones in adult flies exhibit severe lipid droplet accumulations in glial cells and neurodegeneration.

(Liu et al., 2017)

Marf^B mutants exhibit abundant lipid droplet accumulations in pigment and epithelial glia. In addition to the retina, lipid droplets also accumulate in the epithelial glia of the lamina.

Marf^B mutant visual system clones (generated with hid^GMR.PG) exhibit lipid droplet accumulation in the glia.

The morphology of Marf^B mutant photoreceptors is mostly normal or only mildly affected at day 1. They begin to degenerate several days after eclosion, with elongated or diffuse rhabdomeres. One-day old Marf^B clones exhibit approximately 10 lipid droplets per ommatidium. Upon aging, these clones display a significant decrease in the number of lipid droplets.

(Liu et al., 2015)

Homozygotes die as third instar larvae after an extended larval period of 18-21 days.

Homozygous clones in the eye result in electroretinogram defects, including a reduction in amplitude. Mutant photoreceptor cells show a severe loss of mitochondria in their terminals. The mitochondria that are present are significantly smaller than normal.

Mutant larvae show mitochondrial trafficking defects. Levels of mitochondria in the ventral nerve cord neuropil are reduced and those that are present mostly form clumps in the soma and the initial segments of axons. Distal axon segments (in abdominal segment A5) contain far fewer mitochondria than more proximal segments (in segment A3).

Third instar larval neuromuscular junctions show morphological defects. The number of boutons is increased and they show increased clustering, while they are severely reduced in size compared to wild type. The boutons contain almost no mitochondria, in contrast to wild type.

The neuromuscular junctions of Marf^B/Marf^E larvae have normal electrophysiological properties when stimulated at low frequency (0.2 Hz): evoked excitatory junction potential (EJP) amplitude, miniature EJP amplitude and quantal content are all normal. However, upon high frequency stimulation (10Hz for 10 minutes), the mutant neuromuscular junctions are unable to sustain a response, with the EJP amplitude progressively decreasing over time. Endocytosis appears unaffected in the mutant neuromuscular junctions.

Mutant wandering third instar larvae have a significantly reduced number of lipid droplets per ring gland compared to controls. Ultrastructurally, the ring gland cells have a fragmented endoplasmic reticulum (ER) and morphologically abnormal mitochondria. The contacts between the mitochondria and the ER, between the ER and lipid droplets, and between the mitochondria and lipid droplets are all severely reduced compared to wild type.

(Sandoval et al., 2014)

External Data

Linkouts

Interactions

Show genetic interaction network for Enhancers & Suppressors

Phenotypic Class

Suppressed by

Statement

Reference

Marf^B has abnormal neuroanatomy | somatic clone | adult stage phenotype, suppressible by Bsg^SH1217/Bsg[+]

(Liu et al., 2017)

Marf^B has abnormal neuroanatomy | somatic clone | adult stage phenotype, suppressible by Fatp1^KK104809/Scer\GAL4^ey.PU

(Liu et al., 2017)

Marf^B has abnormal neuroanatomy | somatic clone | adult stage phenotype, suppressible by Fatp1^HMC03111/Scer\GAL4^ey.PU

(Liu et al., 2017)

Marf^B has abnormal neuroanatomy | somatic clone | adult stage phenotype, suppressible by Fatp1^HMC03960/Scer\GAL4^ey.PU

(Liu et al., 2017)

Marf^B has abnormal neuroanatomy | somatic clone | adult stage phenotype, suppressible by Fatp1^HMC04206/Scer\GAL4^ey.PU

(Liu et al., 2017)

Marf^B has abnormal neuroanatomy | somatic clone | adult stage phenotype, suppressible by Fatp1^k10307/Fatp[+]

(Liu et al., 2017)

Marf^B has abnormal neuroanatomy | somatic clone | adult stage phenotype, suppressible by Sln^GD1940/Scer\GAL4^ey.PU

(Liu et al., 2017)

Marf^B has abnormal neuroanatomy | somatic clone | adult stage phenotype, suppressible by Sln^KK104306/Scer\GAL4^ey.PU

(Liu et al., 2017)

Marf^B has abnormal neuroanatomy | somatic clone | adult stage phenotype, suppressible by out^GD3448/Scer\GAL4^ey.PU

(Liu et al., 2017)

Marf^B has abnormal neuroanatomy | somatic clone | adult stage phenotype, suppressible by out^KK104187/Scer\GAL4^ey.PU

(Liu et al., 2017)

Marf^B has abnormal neuroanatomy | somatic clone | adult stage phenotype, suppressible by Sln^D1/Sln[+]

(Liu et al., 2017)

Suppressor of

Statement

Reference

Marf^B/Marf[+] is a suppressor | partially of abnormal locomotor behavior | adult stage phenotype of Scer\GAL4^da.G32, fwd^GL00145

(Terriente-Felix et al., 2020)

Other

Statement

Reference

Marf^B, Sod1^G85R has lethal phenotype

(Nemtsova et al., 2023)

Phenotype Manifest In

Suppressed by

Statement

Reference

Marf^B has adult optic lobe glial cell | somatic clone phenotype, suppressible by Sln^GD1940/Scer\GAL4^ey.PU

(Liu et al., 2017)

Marf^B has lipid droplet | somatic clone | adult stage phenotype, suppressible by Sln^GD1940/Scer\GAL4^ey.PU

(Liu et al., 2017)

Marf^B has photoreceptor | somatic clone | adult stage | progressive phenotype, suppressible by Sln^GD1940/Scer\GAL4^ey.PU

(Liu et al., 2017)

Marf^B has adult optic lobe glial cell | somatic clone phenotype, suppressible by Sln^KK104306/Scer\GAL4^ey.PU

(Liu et al., 2017)

Marf^B has lipid droplet | somatic clone | adult stage phenotype, suppressible by Sln^KK104306/Scer\GAL4^ey.PU

(Liu et al., 2017)

Marf^B has photoreceptor | somatic clone | adult stage | progressive phenotype, suppressible by Sln^KK104306/Scer\GAL4^ey.PU

(Liu et al., 2017)

Marf^B has adult optic lobe glial cell | somatic clone phenotype, suppressible by out^GD3448/Scer\GAL4^ey.PU

(Liu et al., 2017)

Marf^B has lipid droplet | somatic clone | adult stage phenotype, suppressible by out^GD3448/Scer\GAL4^ey.PU

(Liu et al., 2017)

Marf^B has photoreceptor | somatic clone | adult stage | progressive phenotype, suppressible by out^GD3448/Scer\GAL4^ey.PU

(Liu et al., 2017)

Marf^B has adult optic lobe glial cell | somatic clone phenotype, suppressible by out^KK104187/Scer\GAL4^ey.PU

(Liu et al., 2017)

Marf^B has lipid droplet | somatic clone | adult stage phenotype, suppressible by out^KK104187/Scer\GAL4^ey.PU

(Liu et al., 2017)

Marf^B has photoreceptor | somatic clone | adult stage | progressive phenotype, suppressible by out^KK104187/Scer\GAL4^ey.PU

(Liu et al., 2017)

Marf^B has adult optic lobe glial cell | somatic clone phenotype, suppressible by Sln^D1/Sln[+]

(Liu et al., 2017)

Marf^B has lipid droplet | somatic clone | adult stage phenotype, suppressible by Sln^D1/Sln[+]

(Liu et al., 2017)

Marf^B has photoreceptor | somatic clone | adult stage | progressive phenotype, suppressible by Sln^D1/Sln[+]

(Liu et al., 2017)

Marf^B has adult optic lobe glial cell | somatic clone phenotype, suppressible | partially by Bsg^SH1217/Bsg[+]

(Liu et al., 2017)

Marf^B has lipid droplet | somatic clone | adult stage phenotype, suppressible | partially by Bsg^SH1217/Bsg[+]

(Liu et al., 2017)

Marf^B has photoreceptor | somatic clone | adult stage | progressive phenotype, suppressible by Bsg^SH1217/Bsg[+]

(Liu et al., 2017)

Marf^B has adult optic lobe glial cell | somatic clone phenotype, suppressible by Fatp1^KK104809/Scer\GAL4^ey.PU

(Liu et al., 2017)

Marf^B has lipid droplet | somatic clone | adult stage phenotype, suppressible by Fatp1^KK104809/Scer\GAL4^ey.PU

(Liu et al., 2017)

Marf^B has photoreceptor | somatic clone | adult stage | progressive phenotype, suppressible by Fatp1^KK104809/Scer\GAL4^ey.PU

(Liu et al., 2017)

Marf^B has adult optic lobe glial cell | somatic clone phenotype, suppressible by Fatp1^HMC03111/Scer\GAL4^ey.PU

(Liu et al., 2017)

Marf^B has lipid droplet | somatic clone | adult stage phenotype, suppressible by Fatp1^HMC03111/Scer\GAL4^ey.PU

(Liu et al., 2017)

Marf^B has photoreceptor | somatic clone | adult stage | progressive phenotype, suppressible by Fatp1^HMC03111/Scer\GAL4^ey.PU

(Liu et al., 2017)

Marf^B has adult optic lobe glial cell | somatic clone phenotype, suppressible by Fatp1^HMC03960/Scer\GAL4^ey.PU

(Liu et al., 2017)

Marf^B has lipid droplet | somatic clone | adult stage phenotype, suppressible by Fatp1^HMC03960/Scer\GAL4^ey.PU

(Liu et al., 2017)

Marf^B has photoreceptor | somatic clone | adult stage | progressive phenotype, suppressible by Fatp1^HMC03960/Scer\GAL4^ey.PU

(Liu et al., 2017)

Marf^B has adult optic lobe glial cell | somatic clone phenotype, suppressible by Fatp1^HMC04206/Scer\GAL4^ey.PU

(Liu et al., 2017)

Marf^B has lipid droplet | somatic clone | adult stage phenotype, suppressible by Fatp1^HMC04206/Scer\GAL4^ey.PU

(Liu et al., 2017)

Marf^B has photoreceptor | somatic clone | adult stage | progressive phenotype, suppressible by Fatp1^HMC04206/Scer\GAL4^ey.PU

(Liu et al., 2017)

Marf^B has photoreceptor | somatic clone | adult stage | progressive phenotype, suppressible by Fatp1^k10307/Fatp[+]

(Liu et al., 2017)

Marf^B has lipid droplet phenotype, suppressible by Scer\GAL4^Feb36/Hsap\MFN2^UAS.cDa

(Sandoval et al., 2014)

Marf^B has ring gland phenotype, suppressible by Scer\GAL4^Feb36/Hsap\MFN2^UAS.cDa

(Sandoval et al., 2014)

NOT suppressed by

Statement

Reference

Marf^B has lipid droplet phenotype, non-suppressible by Scer\GAL4^Feb36/Hsap\MFN1^UAS.cDa

(Sandoval et al., 2014)

Marf^B has ring gland phenotype, non-suppressible by Scer\GAL4^Feb36/Hsap\MFN1^UAS.cDa

(Sandoval et al., 2014)

Marf^B has NMJ bouton phenotype, non-suppressible by Scer\GAL4^Feb36/Hsap\MFN2^UAS.cDa

(Sandoval et al., 2014)

Additional Comments

Genetic Interactions

Statement

Reference

Expression of any of the following: Sln^GD1940, Sln^KK104306, out^GD3448, out^KK104187, Fatp^KK104809, Fatp^HMC03111, Fatp^HMC03960 or Fatp^HMC04206 in the ey>flip whole-eye clones mutant for Marf^B suppresses the lipid droplet accumulation in retinal glial cells in adult flies and also improves the photoreceptor degeneration phenotype. Significant amelioration of both phenotypes is also observed upon combination with one copy of either Sln^D1 or Bsg^SH1217 and the neurodegeneration phenotype is improved also by Fatp^k10307 heterozygosity.

(Liu et al., 2017)

A bsk¹ heterozygous background is sufficient to ameliorate the lipid droplet accumulation displayed in Marf^B mutants.

A SREBP¹⁸⁹ heterozygous background is sufficient to ameliorate the lipid droplet accumulation displayed in Marf^B mutants.

Visual system knockdown of bsk, through expression of bsk^GD10555 under the control of Scer\GAL4^ey.PH in a Marf^B mutant background significantly reduces lipid droplet accumulation.

Expression of Lip4^Scer\UAS.cLa in Marf^B mutant clones partially restores the shape, density and number of identifiable rhabdomeres, indicating that reducing lipid droplet accumulation partially alleviates neurodegeneration.

Expression of bmm^Scer\UAS.cGa in Marf^B mutant clones partially restores the shape, density and number of identifiable rhabdomeres, indicating that reducing lipid droplet accumulation partially alleviates neurodegeneration.

(Liu et al., 2015)

Xenogenetic Interactions

Statement

Reference

Expression of Hsap\SOD1^Scer\UAS.cPa under the control of Scer\GAL4^da.G32 in Marf^B mutant larvae reduces the overall level of reactive oxygen species and considerably suppresses the lipid droplet accumulation seen in these flies.

(Liu et al., 2015)

Expression of Hsap\MFN2^Scer\UAS.cDa under the control of Scer\GAL4^Feb36 restores the number of lipid droplets per ring gland to normal in Marf^B wandering third instar larvae. However, the increase in bouton number seen at the neuromuscular junction in Marf^B larvae is not rescued.

Expression of Hsap\MFN1^Scer\UAS.cDa under the control of Scer\GAL4^Feb36 does not rescue the reduced number of lipid droplets per ring gland seen in Marf^B wandering third instar larvae.

(Sandoval et al., 2014)

Complementation and Rescue Data

Rescued by

Marf^B is rescued by Marf^Tag:HA

(Sandoval et al., 2014)

Marf^B is rescued by Marf^{UAS.cSa.Tag:HA}/Scer\GAL4^Tub.PU

(Sandoval et al., 2014)

Marf^B is rescued by Scer\GAL4^Feb36/Marf^{UAS.cSa.Tag:HA}

(Sandoval et al., 2014)

Partially rescued by

Marf^B is partially rescued by Marf^{UAS.cSa.Tag:HA}/Scer\GAL4^Toll-6-D42

(Sandoval et al., 2014)

Not rescued by

Marf^B is not rescued by Marf^{UAS.cSa.Tag:HA}/Scer\GAL4^Mef2.PU

(Sandoval et al., 2014)

Comments

Expression of Marf^{Scer\UAS.cSa.T:Ivir\HA1} under the control of Scer\GAL4^D42 rescues the mitochondrial trafficking defects seen in the axons of Marf^B mutant larvae. The increase in bouton number seen at the neuromuscular junction is partially rescued.

Expression of Marf^{Scer\UAS.cSa.T:Ivir\HA1} under the control of either Scer\GAL4^tub.PU or Scer\GAL4^Feb36 rescues the increase in bouton number seen at the neuromuscular junction in Marf^B larvae, while expression under the control of Scer\GAL4^Mef2.PU does not.

Expression of Marf^{Scer\UAS.cSa.T:Ivir\HA1} under the control of Scer\GAL4^Feb36 rescues the reduction in lipid droplet number seen in the ring glands of Marf^B wandering third instar larvae.

(Sandoval et al., 2014)

Images (0)

Mutant

Wild-type

Stocks (1)

Bloomington

67154

y¹ w^* Marf^B P{neoFRT}19A/FM7c, P{GAL4-Kr.C}DC1, P{UAS-GFP.S65T}DC5, sn⁺

Notes on Origin

Discoverer

External Crossreferences and Linkouts ( 0 )

Synonyms and Secondary IDs (6)

Reported As

Symbol Synonym

Marf^B

(Nemtsova et al., 2023, Graves et al., 2020, Ponte et al., 2020, Terriente-Felix et al., 2020, Liu et al., 2017, Liu et al., 2015, Sandoval, 2015.5.4, Sandoval et al., 2014)

XE15B

(Graves et al., 2020)

XJZK076

(Graves et al., 2020)

dMfn^B

(Sênos Demarco et al., 2019)

marf(B)

(Shen et al., 2021)

marf^B

(Chew et al., 2021)

Name Synonyms

Secondary FlyBase IDs

References (11)

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