Early L(1)sc expression: Are there L(1)sc equivalence groups?

Stage 98 L(1)sc+ cells

Early Stage 10All posterior cells L(1)sc+

9-10 L(1)sc+ cells + MP3&4Total of 11 -12 L(1)sc+ cells

Stage 10: 2 glia underneath MP3lighter L(1)sc expression7 lsc+ cells around MP4Total of 11 l(1)sc+ cells

Lethal of Scute is Present in MPs and their Neuronal Progeny from Stages 9-11

L(1)Sc pdm2/nub merge

Stage 10

Stage 11

Stage 11

Stage 12

Present in PMG (s10-12)

Present in MNB

Present in all MPs (MP4, MP3, MP1, MP5, MP6) and newly divided neurons (H-cell, H-cell sib; mVUM5,6 and iVUM5,6)

Levels are asymmetric between H-cell and H-cell sib and between mVUM5 and iVUM5

l(1)sc may play a role in both neural precursor formation and establishing different daughter fates

Lethal of Scute is Present in MNB

L(1)sc wor

Reduced Numbers of Neurons are Present in AS-C Mutants

6 elav+ cells present from late 11-16Suggests that reduced numbers of neurons not due to cell death, but less neurons are generated

Stage 12 Stage 14 Stage 16W

ild -t

ype

Df(1

)scB5

7

AS-C Genes are Required for wor Expression

wor: MNBSuggests MNB does not form and does not produce its 8 progeny

wor merge

Wild

-typ

eD

f(1)s

cB57

CG8965 and wrapper are unaffected in AS-C mutants

wrapperCG8965

scB57: 5 CG8965+ cells/seg3.13 wrapper+ CG8965- cells/segn= 8 seg

High levels of wrapper did not always equal CG8965+ cells

wt: 3 PMG/seg @ s14 n=2

AS-C genes are Required for tbh Expression

4 5 6

mVUM

Tbh Cas TkriVUM

Cas(mVUM4,5; iVUM4,5)

Wild

-typ

eD

f(1)s

cB57

Tbh(mVUMs) merge

Tkr(mVUM6; iVUM6)

60% 50%

Suggest that mVUM6 and iVUM6 are present 60%

AS-C Phenotype : Precursor Formation and Neuron-Specific Control

MP1MP1 H-cell H-cellsib mVUM iVUM

AMG AMG AMG AMG

AMG MP3

PMG PMG

MNB

PMGPMG

MP4 MP5 MP6MP1AMG

L(1)sc

Notch

Numb

Neither Notch nor AS-C

Both L(1)sc and Notch

MNBp

Wild-type

AS-C Phenotype : Precursor Formation and Neuron-Specific Control

MP1MP1H-cell

sib iVUM

AMG AMG AMG AMG

AMG MP3

PMG PMG

MNB

PMGPMG

MP4 MP5 MP6MP1AMG

L(1)sc

Notch

Numb

Neither Notch nor AS-C

Both L(1)sc and Notch

AS-C mutant

X X

4 pdm2/nub+ Neurons are Present in AS-C mutants

pdm2/nub: MP1s, H-cell, H-cell sib

pdm2/nub

Stage 14

merge

Wild

-typ

eD

f(1)s

cB57

MP1MP1 H-cell H-cellsib mVUM iVUM

MP3 MP4 MP5 MP6MP1

AS-C Genes are Required for ple Expression

pdm2/nub: MP1s, H-cell & H-cell sib presentMP1 and H-cell sib gene expression unaffectedAS-C genes required for H-cell specific gene expression

Lim3 (MP1s)

CG13565 (H-cell sib)

ple (H-cell)

Wild

-typ

eD

f(1)s

cB57

H-cell H-cellsib

MP3MP1

MP1MP1

AS-C mutants

ac sc l(1)sc ase

D(f)sc 19X-ray derivative of In(1)ac3 pt mutation causes sc to lack C termSc protein nonfunctionalRearrangement that separates all 5’ seq of ac

Df(1)sc B57

ac sc l(1)sc aseX X

X X X X

X

Scute is Present in MPs, but not Neurons from Stages 10-11

Sc pdm2/nub merge

Stage 10

Stage 11

Stage 11

Stage 11

Present in PMG (s10-11)

Present in MP3, MP5, MP1, MP6, and MNB prior to division and is absent from newly divided neurons

May play a role in neural precursor formation, but not in establishing different daughter fates

Achaete Expression

Ac pdm2/nub merge

Stage 10

Stage 11

Stage 11

Stage 12

Present in MP1 and transiently in MP5, MP6, and MNB

Remains on in MP1 neurons to end of embryogenesis

May play a role in precursor formation and in MP1 neuron development